Answer:
B
Explanation:
Correct on Edge
Suppose you have 56.8 g of sulfur (S), how many moles of sulfur do you have? (4 points)
We have 1.77 moles of sulfur in 56.8 g of sulfur. It is a fundamental unit of measurement in the International System of Units (SI) and is defined as the amount of substance that contains the same number of entities as there are in 12 grams of carbon-12.
First, we need to use the formula:
Number of moles = Mass / Molar mass
In this case, the mass of sulfur is 56.8 g, and the molar mass of sulfur is 32.06 g/mol. Substituting these values into the formula, we get:
Number of moles = 56.8 g / 32.06 g/mol
Number of moles = 1.77 mol (rounded to two decimal places)
Therefore, we have 1.77 moles of sulfur in 56.8 g of sulfur. It is important to note that the number of moles is a measure of the amount of substance and is used extensively in chemistry calculations.The entities can be atoms, molecules, or ions, depending on the substance being measured.
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During a recent lab a chemist titrates a 35.0 gram sample of sulfuric acid cleaner (used to clean metals) using a 0.25 M solution of potassium hydroxide. She uses a total of 142.5 mL of base to reach the endpoint for the bromthymol blue indicator.
a.
How many grams of sulfuric acid are in the sample?
b. The label on the cleaner says it is a 3.00% by mass solution. What is the % error for this experiment?
a) There are approximately 1.75 grams of sulfuric acid in the sample.
b)The % error for this experiment is 66.67%.
The percent error for this experiment is approximately 66.67%.To find the number of grams of sulfuric acid in the sample, we can use the stoichiometry of the balanced chemical equation between sulfuric acid (H2SO4) and potassium hydroxide (KOH).
a.The balanced equation is:H2SO4 + 2KOH → K2SO4 + 2H2O
From the equation, we can see that one mole of sulfuric acid reacts with two moles of potassium hydroxide. Therefore, we need to determine the number of moles of potassium hydroxide used in the titration.
Volume of potassium hydroxide solution used = 142.5 mL = 0.1425 L
Moles of potassium hydroxide used = Molarity × Volume (in liters) = 0.25 M × 0.1425 L = 0.0356 moles
Since the ratio between sulfuric acid and potassium hydroxide is 1:2, the number of moles of sulfuric acid in the sample is half of the moles of potassium hydroxide used:
Moles of sulfuric acid = 0.0356 moles / 2 = 0.0178 moles
To convert moles to grams, we can use the molar mass of sulfuric acid, which is approximately 98.09 g/mol:
Mass of sulfuric acid = Moles × Molar mass = 0.0178 moles × 98.09 g/mol ≈ 1.75 grams
b. To calculate the percent error, we need to compare the experimental value (grams of sulfuric acid calculated in part a) with the expected value based on the labeled concentration.
Expected mass of sulfuric acid = Mass of sample × Percentage by mass = 35.0 g × 0.03 = 1.05 grams
Percent error = (|Experimental value - Expected value| / Expected value) × 100
Percent error = (|1.75 g - 1.05 g| / 1.05 g) × 100 ≈ 66.67%
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If a known amount of the weak acid was stoichiometrically titrated with a solution of NaOH
at a known concentration, it would be possible to isolate the sample as a pure sodium salt. What physical process would allow you to isolate this salt after the acid-base titration occurs in solution?
Spell out the full name of the physical process.
Evaporation followed by distillation is a physical process that would allow you to isolate this salt after the acid-base titration occurs in solution.
Acids are defined as substances which on dissociation yield H+ ions , and these substances are sour in taste. Compounds such as HCl, H₂SO₄ and HNO₃ are acids as they yield H+ ions on dissociation.
According to the number of H+ ions which are generated on dissociation acids are classified as mono-protic , di-protic ,tri-protic and polyprotic acids depending on the number of protons which are liberated on dissociation.They are separated by distillation.
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A hospital saline solution is analyzed to confirm its concentration. A 50.0 mL sample with a mass of 50.320 g is evaporated to dryness. If the solid sodium chloride residue has a
mass of 0.669 g. what is the mass percent and molar concentration of the saline solution?
The mass percent of the sodium chloride in the saline solution is approximately 1.33%. The molar concentration of the saline solution is approximately 0.229 M.
To determine the mass percent and molar concentration of the saline solution, we need to analyze the mass of the sodium chloride residue and the initial mass of the sample.
Mass percent:
The mass percent is calculated by dividing the mass of the sodium chloride residue by the initial mass of the sample and then multiplying by 100%.
Mass percent = (Mass of NaCl / Initial mass of sample) × 100%
Mass of NaCl = 0.669 g
Initial mass of sample = 50.320 g
Mass percent = (0.669 g / 50.320 g) × 100% ≈ 1.33%
The mass percent of the sodium chloride in the saline solution is approximately 1.33%.
Molar concentration:
To calculate the molar concentration of the saline solution, we need to determine the number of moles of sodium chloride and the volume of the solution.
Moles of NaCl = Mass of NaCl / Molar mass of NaCl
The molar mass of NaCl is 58.44 g/mol.
Moles of NaCl = 0.669 g / 58.44 g/mol ≈ 0.01144 mol
Since the volume of the sample is given as 50.0 mL, we need to convert it to liters.
Volume of solution = 50.0 mL = 50.0 mL × (1 L / 1000 mL) = 0.0500 L
Now we can calculate the molar concentration (Molarity) using the formula:
Molarity (M) = Moles of solute / Volume of solution (in liters)
Molarity = 0.01144 mol / 0.0500 L ≈ 0.229 M
The molar concentration of the saline solution is approximately 0.229 M.
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What sample at STP has the same number of molecules as 5 L of NO2
Answer:
5l NO
2
at STP
No. of molecules=
22.4
5
mol=
22.4
5
×N
A
molecules
A) 5ℊ of H
2
(g)
No. of moles=
2
5
mol=
2
5
×N
A
molecules
B) 5l of CH
4
(g)
No. of moles of CH
4
=
22.4
5
mol=
22.4
5
N
A
molecules
C) 5 mol of O
2
=5N
A
O
2
molecules
D) 5×10
23
molecules of CO
2
(g)
Molecules of 5l NO
2
(g) at STP=5l of CH
4
(g) molecules at STP
Therefore, option B is correct.
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Which of the following populations would most likely be stable?
the population of weeds in an empty field
the population of almond trees in an orchard
the population of mice in a barn
All of these choices are correct.
The population of weeds in an empty field would most likely be stable
Why will the population of weeds in an empty field most likely be stable?It should be noted that weeds inhabiting an unattended field are expected to sustain relatively constant numbers over time due largely in part to their quick and easy reproductive capabilities.
This is complemented by their comparative resistance towards predation or disease when juxtaposed against other plant types they frequently cohabit with. Weeds can further endure hostile environmental factors better than most plants can, which adds complexity when attempting their control.
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he reaction between solid copper and aqueous silver nitrate produces solid silver and a blue solutions, as represented by the balanced equation shown below. Based on the balances equation, which of the following correctly identifies the oxidation and reduction half- reaction
Cu(s) + 2AgNo3(aq)-> Cu+2(aq) + 2e-
The equation shown in the second option is the correct equation of oxidation and reduction.
What is oxidation and reduction?A substance loses electrons or undergoes oxidation when it becomes more oxidized. It entails a substance's receiving oxygen, losing hydrogen, or gaining electrons from another substance.
A substance receives electrons during reduction, which also lowers its oxidation state. It entails either the addition of hydrogen to a substance, the removal of oxygen from a substance, or the acquisition of electrons from another molecule.
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When 0.695 g of an unknown gas are held in an otherwise-empty 293-mL container, the pressure is 807.4 mmHg at 22°C. What is the molecular mass of the gas?
____g/mol
The molecular mass of the gas is 54 g/mol.
The Ideal gas law is the equation of state of a hypothetical ideal gas. It is a good approximation to the behaviour of many gases under many conditions, although it has several limitations. The ideal gas equation can be written as
PV = nRT
where,
P = Pressure
V = Volume
T = Temperature
n = number of moles
In this equation, number of moles can be replaced by mass divided by molecular mass.
Given,
Mass = 0.695g
Volume = 293ml = 0.293L
Pressure = 807.4mmHg = 807.4/760 atm
Temperature = 22⁰C = 22 +273 = 295K
PV = nRT
(807.4 × 0.293) ÷ 760 = (0.695 × 8.314 × 295) ÷ M
M = (0.695 × 0.0821× 295 ×760) ÷ (807.4 × 0.293)
M= 54 g/ mol
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Name a liquid substance that could be used in the laboratory for dissolving dry mortar on floor tiles
Answer:muriatu acid
Explanation:
What quantity in moles of chlorine gas at 120.0 °C and 33.3 atm would occupy a vessel of 14.0 L?
A vessel of 14.0 L would hold 1.78 moles of chlorine gas at 120.0 °C and 33.3 atm.
The ideal gas law relates the pressure (P), volume (V), temperature (T), and the number of moles (n) of a gas to a constant R known as the universal gas constant. In this equation, P, V, and T are directly proportional to n, which means that as the number of moles of gas increases, so does the pressure, volume, and temperature.
Using the ideal gas law, PV = nRT, we can solve for the number of moles of chlorine gas:
n = PV/RT
First, we need to convert the temperature to Kelvin by adding 273.15:
T = 120.0 + 273.15 = 393.15 K
Next, we can plug in the values we have:
n = (33.3 atm)(14.0 L)/(0.0821 L•atm/mol•K)(393.15 K)
n = 1.78 moles
Therefore, 1.78 moles of chlorine gas at 120.0 °C and 33.3 atm would occupy a vessel of 14.0 L.
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Where does the scientific name of an organism come from?
Answer: the answer is money
Explanation: money=happy person.
The wind moves from_____ pressure area to_____preasure area because of unequal heating and cooling of Earth's land and water surfaces
The wind moves from high pressure area to low pressure area because of unequal heating and cooling of Earth's land and water surfaces
The movement of air or wind from a high pressure area to a low pressure area is due to the difference in air pressure between the two regions. High-pressure areas are characterized by relatively dense and cooler air that tends to sink, while low-pressure areas have relatively warm and less dense air that rises.
These differences in air pressure arise due to the unequal heating and cooling of the Earth's land and water surfaces. For instance, regions near the equator receive more direct sunlight, and hence, the air gets heated more quickly, leading to the formation of a low-pressure area.
Conversely, regions near the poles receive less direct sunlight, and hence, the air is cooler and denser, leading to the formation of a high-pressure area. As a result, air moves from high pressure to low pressure areas, creating winds and affecting the global climate.
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PLEASE HELP ME WITH THE QUESTION IN THE IMAGE BELOW I WILL MAKE YOU BRAINLIEST AND GIVE YOU 17 POINTS!
Answer:
The sound playing from the first graph is louder, while the sound from the second graph is deeper, both of which have the same pitch.
Explanation:
First let's analyze the graphs,
Comparing the first graph to the second
Concluding from the above observations, the sound playing from the first graph is louder, while the sound from the second graph is deeper, both of which have the same pitch.
1. Show a correct numerical setup for calculating the molarity of the sodium hydroxide solution.
2. Determine both the total volume of HCl(aq) and the total volume of NaOH(aq) used in the titration.
The molarity of the NaOH is 0.25 M
The total volume of the NaOH used is 3.8 mL
Total volume of the HCl used is 9.5 mL
What is titration?Total volume of HCl = Final burette reading - Initial burette reading
= 25 mL - 15.5 mL = 9.5 mL
Total volume of NaOH used = 8.80 mL - 5.00 mL = 3.8 mL
Number of moles of the HCl = 9.5/1000 * 0.1 M
= 0.00095 moles
Since the reaction is 1:1
molarity of the NaOH = Number of moles /Volume
= 0.00095 moles * 1000/3.8
= 0.25 M
This is the molarity of the NaOH that is involved.
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i need help answering number 1 and number 3 50 points!!
The removal of hydrogen or any other electropositive element, or the addition of oxygen, is said to be the process of oxidation in classical or earlier concepts. An atom or ion gains one or more electrons during the process of reduction.
1. The oxidation half-reaction of copper is:
Cu → Cu²⁺ + 2e⁻
The reduction half is:
Cu²⁺ + 2e⁻ → Cu
3. An anode in electrochemistry is, in its simplest form, the site of an oxidation reaction. Due to the anode's electrical potential, negative ions or anions usually react there and release electrons. After that, these electrons ascend and enter the drive circuit.
In chemistry, the cathode is referred to as the electrode where reduction takes place. In an electrochemical cell, this is typical. Here, the cathode is negative because the cell's electrical energy supply causes chemical molecules to break down.
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At 10°C, the gas in a cylinder has a volume of 0.250 L. The gas is allowed to expand to 0.285 L.
What must the final temperature be for the pressure to remain constant? (Hint °C + 273 = K.)
323 K
248 K
282 K
284 K
The final temperature must be approximately 248 K for the pressure to remain constant. B is correct option.
We can use the combined gas law to solve this problem, which states that: (P1V1)/T1 = (P2V2)/T2
where P1 and V1 are the initial pressure and volume, respectively, T1 is the initial temperature, P2 and V2 are the final pressure and volume, respectively, and T2 is the final temperature.
We know that the initial volume V1 is 0.250 L and the final volume V2 is 0.285 L. The pressure P is constant, so we can set P1 = P2. The initial temperature T1 is 10°C, which is equivalent to 283 K (10°C + 273 = 283 K). Substituting these values into the combined gas law and solving for T2, we get: (P1V1)/T1 = (P2V2)/T2
(P1V1) = (P2V2)(T1/T2)
T2 = (P2V2)(T1)/(P1V1)
T2 = (P1V1)(T2)/(P2V2)
T2 = (283 K × 0.250 L)/(0.285 L)
T2 = 248 K.
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- A company in the plastics-making industry is currently using an additive in their
manufacturing process. This additive, when combined with any common plastic resin,
renders an end-product that can be metabolized into inert biomass by the
communities of microorganisms commonly found almost everywhere on Earth.
Which of the following is an environmental benefit of the end-product produced in this
plastic-making process?
try and find a better answer or ask ur teacher please
24.1.4 Quiz: Electric Force
Question 5 of 5
What could you do to increase the electric force between two charged
particles by a factor of 16?
A. Reduce one particle's charge by a factor of 4.
B. Increase one particle's charge by a factor of 16.
C. Increase one particle's charge by a factor of 4.
D. Reduce one particle's charge by a factor of 16.
The electric force increases by a factor of 16 when the distance is reduced by a factor of 4, hence option A is correct.
The nucleus and electrons are drawn to one another by the electric force. The void created by a positive or negative charge is referred to as an electric field, since it generates a field there.
The electric force is inversely linked to the square of the separation distance and directly connected to the product of the charges. It would be possible to treble the force by doubling both charges.
Reduce one particle's charge by a factor of 4, to increase the electric force between two charged particles by a factor of 16.
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If a solution has a poh of 7, what is the [OH-] equal to?
The pOH of a solution can be calculated using the formula: pOH = -log[OH-]. To find the [OH-] concentration when the pOH is 7, we need to convert the pOH value to the OH- concentration.
Starting with pOH = 7, we can rearrange the equation to find [OH-]. Taking the antilog of both sides, we get 10^(-pOH) = 10^(-7). This simplifies to [OH-] = 10^(-7) or 0.0000001 M.
Therefore, the [OH-] concentration in the solution with a pOH of 7 is 0.0000001 M or 1 x 10^(-7) M.
It's worth noting that the pOH and pH of a solution are related by the equation: pH + pOH = 14. In this case, if the pOH is 7, the pH of the solution would be 14 - 7 = 7.
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I NEED HELP ASAP
Considering the setup from the previous problem, calculate the number of moles of salt in 6.37 grams.The molecular weight of table salt, NaCl, is 58.5 g/mol. Type in your answer below using the correct number of significant figures.
6.37 g NaCl = ?
The number of moles of the sodium chlroide from the calculation is 0.11 moles.
What is the mole?
We can connect a substance's mass to its particle count using the concept of a mole. A material's molar mass, which is measured in grams per mole, is the mass of one mole of that substance. One mole of carbon-12 atoms, for instance, weighs 12 grams according to its molar mass of 12 grams/mol.
We have that;
Number of moles = Mass/molar mass
mass = 6.37 grams
Molar mass = 58.5 g/mol
Number of moles = 6.37 g/58.5 g/mol
= 0.11 moles
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helpp me please i need help
The phase changes are;
Fusion- Exothermic
Sublimation - Exothermic
Condensation - Endothermic
Vaporization - Exothermic
Freezing - Endothermic
What is a phase change?When a substance changes from one phase or state of matter to another, this is referred to as a phase change. The solid, liquid, and gas states are the three fundamental types of matter. A substance's physical characteristics, including shape, volume, and density, might alter when it goes through a phase shift.
Temperature and pressure variations are the primary causes of phase shifts. The particular conditions necessary for a phase change to take place vary depending on the substance. As phase shifts affect the behavior, properties, and uses of diverse materials
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If a snail crawls 55 inches per day, how many centimeters will he crawl in 23 days?
Group of answer choices
5.0X102 cm
1.06 cm
3.2X103 cm
6.1 cm
2.0X10-3 cm
If a snail crawls 55 inches per day ,the snail will crawl approximately [tex]3.2 * 10^3 centimeters.[/tex]
To convert inches to centimeters, we need to use the conversion factor: 1 inch = 2.54 centimeters.
First, let's calculate the distance the snail crawls in inches in 23 days. We can multiply the daily distance by the number of days:
Distance in inches = 55 inches/day × 23 days = 1265 inches.
Now, to convert the distance from inches to centimeters, we multiply the distance in inches by the conversion factor:
Distance in centimeters = 1265 inches × 2.54 cm/inch = 3215.1 cm.
Rounding to the appropriate number of significant figures, the snail will crawl approximately 3215 cm or [tex]3.2 * 10^3 centimeters.[/tex] in 23 days.
Therefore, the answer is Option 3:[tex]3.2 * 10^3 centimeters.[/tex]
This means that in 23 days, the snail will crawl approximately[tex]3.2 * 10^3 centimeters.[/tex]
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Define personality and identify influences on personality. Next, describe the characteristics that may indicate someone has
a personality disorder.
Personality is the reflection of the behavioral, cognitive, and emotionalmake up of a person. The factors that are responsible for the outcome of personality are influenced by the biological and environmental factors. If the person behaves abnormally, shows anxiety, impulsiveness, emotional disturbance, not able to take decisions, and quarrelsome all these factors can be indicative of personality disorder. Learn more about personality:
Rank the acids from strongest to weakest. To rank items as equivalent, overlap them.
HCl
HI
H2O
H2S
The ranking of the acids from strongest to weakest is: B) HI > A) HCl > D) H2S > C) H2O
To rank the acids from strongest to weakest, we need to consider their acid dissociation constants (Ka) or their respective pKa values. The lower the pKa value, the stronger the acid.
Here are the acids listed from strongest to weakest:
B) HI: Hydroiodic acid has a very low pKa value, indicating that it is a strong acid. It readily dissociates in water to release hydrogen ions (H+). HI is stronger than the other acids in the list.
A) HCl: Hydrochloric acid is also a strong acid with a low pKa value. It dissociates almost completely in water to produce H+ ions.
D) H2S: Hydrogen sulfide is a weak acid compared to HI and HCl. It has a higher pKa value, indicating that it does not dissociate as completely in water as the previous two acids. However, it still donates some hydrogen ions and exhibits acidic properties.
C) H2O: Water is considered a neutral substance with a pKa of 14. It can act as a weak acid or a weak base depending on the reaction it is involved in. In this list, it is the weakest acid. While it can donate a proton to form H+ ions, its tendency to do so is significantly lower compared to the other acids.
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how many moles of Na3AlO3 can be formed from 7.24 moles of NaOH
7.24 moles of NaOH can produce 3.62 moles of Na3AlO3.
To determine the number of moles of Na₃AlO₃ formed from 7.24 moles of NaOH, we need to consider the balanced chemical equation for the reaction. The reaction between NaOH and Al₂(SO₄)₃ produces Na₃AlO₃ and H₂O.
The balanced chemical equation is:
6 NaOH + Al₂(SO₄)₃ → 3 Na₃AlO₃ + 3 H₂O
From the equation, we can see that 6 moles of NaOH react to produce 3 moles of Na₃AlO₃. This means that the mole ratio of NaOH to Na₃AlO₃ is 6:3, which simplifies to 2:1.
Therefore, if we have 7.24 moles of NaOH, we can calculate the moles of Na₃AlO₃ formed by dividing the number of moles of NaOH by 2:
7.24 moles NaOH / 2 = 3.62 moles Na₃AlO₃
Thus, 7.24 moles of NaOH can produce 3.62 moles of Na₃AlO₃ according to the balanced chemical equation.
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what causes an object to have a charge?
Answer:
An electrical charge is created when electrons are transferred to or removed from an object.
Explanation:
Because electrons have a negative charge, when they are added to an object, it becomes negatively charged. When electrons are removed from an object, it becomes positively charged.
What is the molarity of a solution which contains 58.4 g of CsF dissolved in 500. mL of solution?
Answer:
0.768 mol/L
Explanation:
Given, mass of CsF = 58.4 gm
Molar mass of CsF = Molar mass of Cs + Molar mass of F
= 133 u + 19 u
= 152 u
Number of moles of CsF = Mass of CsF/ Molar mass of CsF
= 58.4/152 mol
Given, volume of solution = 500 mL = 0.5 L
Molarity of solution = moles of solute/volume of solution
= (58.4/152) mol / 0.5 L
= 58.4 * 2/152 mol/L
= 0.768 mol/L
Lewis structure AgBr2
Answer:
Br-Ag-Br
Explanation:
Describe properties of the 4 major bond types.
The four major bond types are ionic bonds, covalent bonds, metallic bonds, and hydrogen bonds. It influences boiling and melting points, solubility, and the structure and function of complex molecules like proteins and DNA.
Each bond type has distinct properties:Ionic Bonds: Ionic bonds form between ions of opposite charges. They have high melting and boiling points and are typically formed between metals and nonmetals. Ionic compounds are held together by strong electrostatic attractions, resulting in solid crystalline structures. They are often soluble in water and conduct electricity when dissolved or molten.
Covalent Bonds: Covalent bonds involve the sharing of electrons between atoms. They can be polar or nonpolar, depending on the electronegativity difference between the atoms. Covalent compounds have varying melting and boiling points, but they are generally lower than those of ionic compounds. They can exist as gases, liquids, or solids, and their properties depend on factors like molecular size and intermolecular forces.
Metallic Bonds: Metallic bonds occur in metals, where valence electrons are delocalized and form a "sea" of mobile electrons. Metallic compounds have high thermal and electrical conductivity due to the free movement of electrons. They are malleable and ductile, allowing metals to be shaped into various forms. Metallic bonds result in metallic luster and varying melting points depending on the metal's properties.
Hydrogen Bonds: Hydrogen bonds form between hydrogen atoms and highly electronegative atoms like oxygen, nitrogen, or fluorine. They are relatively weak compared to ionic or covalent bonds. Hydrogen bonding plays a crucial role in the properties of substances such as water and biological molecules.
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How many atoms are in 94 g of NaCl
Answer: 9.78 X 10^223 atoms NaCl
Explanation:
Solve using Stoichiometry.
94 g NaCl X (1mole NaCl/58 gNaCl) X (6.02 X 10^23 atoms NaCl/1mole NaCl) = 9.78 X 10^23 atoms NaCl