Rubidium (Rb) has two isotopes. Using the data in the table below,
calculate the relative atomic mass of Rb. Give your answer to 3 significant
figures.
Answer:
85.6
Explanation:
(72 x 85) + (28 x 87)
-----------------------------
100
= 85.56
= 85.6 (3 s.f.)
How many grams are in 8.50 e 23 formula units of NaCl?
a)82.5 g
b)8.25 g
c)85.0 g
d)91.5 g
Answer:
a)82.5 g
Explanation:
To solve this problem we will use Avogadro's number, which states the number of formula units per mole.
8.50x10²³formula units ÷ 6.023x10²³ formula units/mol = 1.41 molThen we convert 1.41 moles of NaCl to grams, using its molar mass:
1.41 mol NaCl * 58.44 g/mol = 82.4 gThe closest answer is option a).
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Answer:
sorry if this is wrong but B
Explanation:
ITS C
Oxygen, APT, and Glucose
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A 2.00 g sample of ammonia (NH3) reacts with 4.00 g of oxygen (O2) according to the equation 4NH3+5O2→4NO+6H2O. How much excess reactant remains after the reaction has stopped ( knowing that NH3 is the excess reactant )?
Answer:
0.017 moles of ammonia remains after the reaction is stopped.
Explanation:
The reaction is:
4NH₃ + 5O₂ → 4NO + 6H₂O
The first step is to convert the mass to moles, of each reactant:
2 g . 1mol/ 17g = 0.117 moles of NH₃
4 g . 1mol /32g = 0.125 moles of O₂
Ammonia, states the question, is the excess reactant so we can confirm it,
5 moles of oxygen need 4 moles of ammonia to react (by stoichiometry)
Then, 0.125 moles of oxygen may react to (0.125 . 4) / 5 = 0.1 moles
As we have 0.117 moles of ammonia and we need 0.1 moles.
(0.117 - 0.1) = 0.017 moles remains after the reaction is completed.
If we convert the moles to mass we have:
0.017 mol . 17 g /1mol = 0.289 g
how many molecules of NaCl are in 32.5 G
Answer :32,5 g NaCl equal 0,556 moles.
Explanation:
Round the following number to
3 significant figures:
3,545,530
The concept of significant figures are mainly used by scientist and engineer to know the significance of digits in a measurement. Therefore, 3,545,530 upto 3 significant figures is 3.54 x 10³.
What is significant figures?Significant figures are the figures that indicate the degree of accuracy of a value. It tells about the precision of a value. It gives an idea about the digits that are necessary to indicate the experimental value.
Rules for counting significant figures are:
Number between 1 to 9 is always significant
Zeroes after a number has got no significance
Zeroes before a number has got no significance
Zeroes between number has got significance
3,545,530 upto 3 significant figures is 3.54 x 10³.
Therefore, 3,545,530 upto 3 significant figures is 3.54 x 10³.
To learn more about Significant figures, here:
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PLS HURRY MY TEST IS TIMED
Currently, some commercially available explosives are tagged with traceable
radioactive isotopes
chemical markers
cell-signal components
acetone compounds
Answer:chemical markers
Explanation:
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Q3 - Complete the word equation *
1 point
Bromine +
Chlorine
Bromide +
Potassium
Chloride
Bromine +
Potassium
Chloride
Hydrogen
bromide +
Potassium
Chloride
Chlorine +
Potassium
Bromide ->
Frost forming on a car's windshield is a chemical change
True or false
Answer:
True
Explanation:
The reason why is because frost is a result of a chemical reaction
How many grams of oxygen were used if 3.0 moles of aluminum oxide are produced
Answer:
143.9946 g
Explanation:
Plz help, will give brainliest!
Answer:
C
Explanation:
No change.
The total number moles of products = The Total number of reactants
What is equilibrium in scientific terms? I need it broken down as simple as possible please because I don't understand it.
In science, literature, and everything, equilibrium has the same meaning. The meaning simply put, is balance. If you wanted a sentence example, it could be something like:
'He sat down to try and recover his equilibrium.'
Or
'They can't maintain enough equilibrium to ride a bike.'
I hope you understand the meaning now?
For the reaction, ?N2 + ?H2 → ? NH3,
What is the maximum amount of NH3 which could be formed from 12.26 mol of N2 and 2.11 mol of H2? Answer in units of mol.
Explanation:
➢number of moles. Moles and Chemical Reactions. Chapter 4. 3 H2. + N2. →. 2 NH3 ... How many grams of NH3 would form if 2.11 moles of N2 reacted with ...
How does pressure affect an organism plants?
Answer:
Turgor pressure in plants. Turgor pressure within cells is regulated by osmosis and this also causes the cell wall to expand during growth.
Explanation:
I hope that helps
Nitric monoxide (NO) reacts with oxygen gas to form nitrogen dioxide (NO₂), a dark brown gas. If 5.895 mol of NO is mixed with 2.503 mol of O₂,
determine the limiting reagent.
calculate the number of grams of NO₂ produced.
and determine how many grams of excess reagent remain unreacted.
Answer:
Limiting reactant: O2
grams NO2 produced = 230.276 g NO2
grams of NO unused = 26.67 gNO
Explanation:
2NO + O2 --> 2NO2
Step 1: Determine the molar ratio NO:O2
molar ratio NO:O2 = 5.895: 2.503 = 2.35
stoichiometric molar ratio NO:O2 = 2:1
So, O2 is the limiting reactant.
Step2: Determine the grams of NO2:
?g NO2 = moles O2 x (2moles NO2/1 mol O2) x (MM NO2/ 1 mol NO2) = 2.503 x 2 x 46 = 230.276 g NO2
Step 3: Determine the amount of excess reagent unreacted
moles excess NO reacted = moles O2 x (2 moles NO/1 mol O2) = 2.503 x 2 = 5.006 moles NO reacted
moles NO unreacted = total moles NO - moles NO reacted = 5.895-5.006 =0.889 moles NO unreacted
mass NO unreacted = moles NO unreacted x MM NO = 0.889 x 30 =26.67 g NO unreacted
balance
Na2O+H2O → NaOH
how do fossils get inside rocks
Explanation:
It to be fossilized, the remains usually to be covered by sediment soon after death. sediment can include the sandy seafloor,lava,and even sticky tar. Over time, minerals in the sediment seep in to remains. The remains become fossilized.
A gas in the form of Bubbles is released is it a chemical change or a physical change
Answer:
The formation of a gas is a clue to chemical changes. The bubbles of gas that you observed form when an antacid is dropped into water is an example of change. Another clue that a chemical change has occurred is the formation of a solid.
Explanation:
1. inside of a cell helps it to maintain its size and shape. 2. When turgor pressure inside of a plant’s cells decreases, the plant begins to 3. Plants grow upward against the downward force of gravity in a process known as 4. Even when plants are placed on their sides, they recognize the force of gravity, and their stems grow and their roots grow ** answers please its on stem scopes on Concept attainment quiz 7.7B Organism Force and Motion**
The gametes are identical to each other and combine to make an identical organism.
True
False
Answer:
true
Explanation:
What is SiCl4 written out?
Answer:
Silicon tetrachloride
Explanation:
1. If you have 5g of pennies how many dozen pennies do you have?
Answer:
15.69 dozen
Explanation:
Mass of penny = 5 g
Dozens of penny =..?
Next, we shall convert 5 g to gross. This can be obtained as follow:
3824 g = 1000 gross
Therefore,
5 g = 5 g × 1000 gross / 3824 g
5 g = 1.3075 gross
Thus, 5 g is equivalent to 1.3075 gross.
Finally, we convert 1.3075 gross to dozen. This can be obtained as follow:
1 gross = 12 dozen
Therefore,
1.3075 gross = 1.3075 gross × 12 dozen / 1 gross
1.3075 gross = 15.69 dozen
Thus, 5 g of penny is equivalent to 15.69 dozen
Why is pathogen a better word choice than "Germ"?
Answer: because its more scientific and "formal"? I guess.
Explanation:
PLEASE HELP ASAP!!! WILL MARK BRAINLIEST!!!! 25 POINTS!!!!! IF YOU"RE JUST GOING TO ANSWER FOR POINTS PLEASE DO NOT I NEED REAL ANSWERS!!!!
2. Which gas law is this experiment investigating? How does your graph represent the gas law under investigation?
3. Using your knowledge of the kinetic molecular theory of gases, describe the relationship between volume and temperature of an ideal gas. Explain how this is reflected in your lab data.
4. Pressure and number of moles remained constant during this experiment. If you wanted to test one of these variables in a future experiment, how would you use your knowledge of gas laws to set up the investigation?
Answer:
2. for number two I asks what the experiment is showing, I need the picture of the experiment.
3. As temperature increases, the particles will gain kinetic energy causing it to move more rapidly and randomly. However, this causes the gas to expand as the particles will have more energy to roam freely. as temperature increases, Volume increases.
4. Im not sure D:
6. The Haber process for making ammonia (NH)
gas from its elements was developed by Fritz Haber
during WWI. Haber hoped to use ammonia as
fertilizer to grow food for Germany during the
Allie's blockade. How many liters of hydrogen
would be required to produce 40.0L of ammonia at
STP? N+H, NH,
Answer:
60 Liters
Explanation:
The equation for this reaction is given as;
N2 + 3H2 → 2NH3
From the reaction;
3 mol of H2 produces 2 mol of NH3
At STP;
1 mol = 22.4 L
This means
67.2 L ( 3 * 22.4) of H2 produces 44.8 L ( 2 * 22.4) of NH3
How many L of H2 would produce 40 L of NH3
67.2 = 44.8
x = 40
Solving for x;
x = 40 * 67.2 / 44.8
x = 60 L
similarities of ancient and modern philosophy
Which substance is a binary acid?
• hydrochloric acid
O phosphoric acid
• nitrous acid
O sulfuric acid
Answer:
hydrochloric acid
Explanation:
Why do metal boats float?
Answer:
I hope this will help you
Explanation:
The air that is inside a ship is much less dense than water. That's what keeps it floating! The average density of the total volume of the ship and everything inside of it (including the air) must be less than the same volume of water.
Please make me brilliant
Solutions of calcium nitrate and sodium chloride are mixed.
Answer:
For example, when water solutions of calcium nitrate and sodium carbonate are mixed, calcium carbonate precipitates from the solution while the other product, sodium nitrate, remains dissolved. It is a precipitate.
Explanation: