Answer:
John Dalton
Explanation:
Both John Dalton and Democritus thought that the atom was an indivisible sphere until J.J. Thompson came out with the plum pudding model. Hope I helped!
adaptive features of aquatic plants
Given 1.67 moles of K, how many moles of KBr are produced?
2 K+ 1 Br2---> 2 KBr
[tex]\displaystyle 1.67 \ mol \ KBr[/tex]
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
BracketsParenthesisExponentsMultiplicationDivisionAdditionSubtractionLeft to RightChemistry
Atomic Structure
MolesStoichiometry
Using Dimensional AnalysisAnalyzing Reactions RxNExplanation:Step 1: Define
[RxN - Balanced] 2K + Br₂ → 2KBr
[Given] 1.67 moles K
[Solve] moles KBr
Step 2: Identify Conversions
[RxN] 2 mol K → 2 mol KBr
Step 3: Stoichiometry
[DA] Set up conversion: [tex]\displaystyle 1.67 \ mol \ K(\frac{2 \ mol \ KBr}{2 \ mol \ K})[/tex][DA] Multiply/Divide [Cancel out units]: [tex]\displaystyle 1.67 \ mol \ KBr[/tex]An empty steel container is filled with 2.0 atm of H₂ and 1.0 atm of F₂. The system is allowed to reach equilibrium according to the reaction below. If Kp = 0.45 for this reaction, what is the equilibrium partial pressure of HF?
The equilibrium partial pressure of HF is 0.55 atm.
The equation of the reaction is;
H2(g) + F2(g) ⇄ 2HF
I 2 1 0
C -x -x +x
E 2 - x 1 - x x
We know that;
pH2 = 2.0 atm
PF2 = 1.0 atm
pHF = ??
Kp = 0.45
So;
Kp = (pHF)^2/pH2. pF2
0.45 = x^2/(2 - x) (1 - x)
0.45 = x^2/x^2 - 3x + 2
0.45(x^2 - 3x + 2) = x^2
0.45x^2 - 1.35x + 0.9 = x^2
0.55 x^2 + 1.35x - 0.9 = 0
x = 0.55 atm
Learn more about equilibrium: https://brainly.com/question/3980297
A triangle has one angle that measures 81° and one that measures 37° what is the measure of a third angle
3. Define the term zwitterion. Draw the structure of alanine and explain why this molecule is a
zwitterion in certain conditions.
Answer:
A zwitterion or a hybrid ion is an ion that has both a positive and negative charge and can act as either a base or an acid.
Explanation:
A zwitterion or a hybrid ion is an ion that has both a positive and negative charge and can act as either a base or an acid. The net charge on a zwitterion is zero since it has equal number of positive and negative charges.
Alanine, is a monoamino monocarboxylica acid that is diprotic when fully protonated. The carboxylic acid group, COOH and the amino group, NH₃⁺, are able to produce one proton each. At a pH equal to the isoelectric point of alanine, it exists mainly in the zwitterionic form with the α-amino group protonated as NH₃⁺ and the α-carboxyl group deprotonated as COO⁻ . This is because at the isoelectric point of alanine (6.0), pI is greater than the acid dissociation constant, pKa of the α-carboxyl group whereas, pI is less than the acid dissociation constant, pKa of the α-amino group, so the two groups are negatively and positively charged respectively.
HELP and give brainlys out to ppl who actually know the answer please help
Answer:
b. snake and earthworm
Explanation:
embryos are different from each other in early stages- all the others look similar
One of the following is not a physical property of iron.
Mark only one oval.
malleability
magnetism
rusting
color
Answer:
Rusting
Explanation:
Rusting is oxidizing iron, which would be a chemical property.
Compare the change in pH with the addition of acid and base to deionized water and to a buffer.
Answer:
case1.
The addition of acid and base leads to a change in pH of the water when adding to deionized water due to fact that acid and bases dissociated in dissolving in water. If the H+ ion increases in the water as acid addition hikes it, it will result in decreasing the pH value. The intensity of the acid also affects the dissociation of the ions.
case2
Buffers are normally formed by weak acid and its conjugate base, and adding acid to the buffer it absorbs the H+ ions so the pH will be lower and adding base or increase of OH- conjugate base resists the pH value to increase.
What is the final volume?
Answer:
Option A. 9.4 L
Explanation:
From the question given above, the following data were obtained:
Initial volume (V₁) = 8 L
Initial temperature (T₁) = 293 K
Final temperature (T₂) = 343 K
Final volume (V₂) =?
V₁ / T₁ = V₂ / T₂
8 / 293 = V₂ / 343
Cross multiply
293 × V₂ = 8 × 343
293 × V₂ = 2744
Divide both side by 293
V₂ = 2744 / 293
V₂ = 9.4 L
Therefore, the final volume of the gas is 9.4 L
PLS HELP THIS IS DUE IN 10 MINS!
Compare and contrast floods and droughts. Give two examples of how they are the same and two examples of how they are different.
Put the following type of radiations in order of increasing energy: red, radio, UV, infrared, blue, and x-ray
Answer: The order of increasing energy is: radio < infrared < red < blue < UV < x rays
Explanation:
Electromagnetic wave is defined as the wave which is associated with both electrical and magnetic component associated with them.
The electromagnetic radiations consist of gamma rays , X rays , Ultraviolet , Visible , Infra red , microwaves and radio waves arranged in order of decreasing frequency and increasing wavelengths. The visible region consists of violet , indigo , blue , green , yellow, orange and red lights in order of decreasing frequency or increasing wavelength
The relationship between energy and frequency of the wave follows the equation:
[tex]E=h\times \nu[/tex]
where,
[tex]\nu[/tex] = frequency of the wave
E = energy of wave
From the above relation, it is visible that energy and frequency follow direct relation. For increase in value of frequency, energy increases and vice-versa.
Thus the order of increasing energy is: radio < infrared < red < blue < UV < x rays
What BEST describes the relation of a new population to an increase in the amount of space it occupies? a - The population will die out
b - The population will remain constant
c - The population will grow exponentially
A severe storm would be most likely to damage a coastal area by causing
A.
volcanoes.
B.
pollution.
C.
erosion.
D.
earthquakes.
A severe storm would be most likely to damage a coastal area by causing pollution. Therefore, the correct option is option B.
What is coastal area?The region where land joins the ocean, or even as a line defining the border between the land as well as the shoreline, is known as the coast, sometimes referred as the coastline and seashore. The terrain of the area's surroundings has an impact on shorelines, as do water-induced erosion processes like wave action.
The length of the shoreline on Earth is about 620,000 kilometers. Natural ecosystems' coasts are significant zones and frequently the site of a diverse range of biodiversity. They are home to significant ecosystems on land, such as freshwater and estuarine wetlands, that are crucial for the survival of bird populations or other land animals. A severe storm would be most likely to damage a coastal area by causing pollution.
Therefore, the correct option is option B.
To know more about coastal area, here:
https://brainly.com/question/14105067
#SPJ3
How many moles are in 2.5L of 1.75 M Na2CO3
Answer: There are 4.375 moles in 2.5 L of 1.75 M [tex]Na_2CO_3[/tex]
Explanation:
To calculate the number of moles for given molarity, we use the equation:
[tex]\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}[/tex]
Molarity of solution = 1.75 M
Volume of solution = 2.5 L
Putting values in equation , we get:
[tex]1.75M=\frac{\text{Moles of} Na_2CO_3}{2.5L}\\\\\text{Moles of }Na_2CO_3=1.75mol/L\times 2.5L=4.375mol[/tex]
What volume of 1.75 M hydrochloric acid (HCl aq) must be diluted with water to prepare 0.500 L of 0.250 M hydrochloric acid?
Answer:
[tex]V_1=0.0714L[/tex]
Explanation:
Hello there!
In this case, since we need to dilute the 1.75-M HCl, and the total number of moles remain unchanged, we can write:
[tex]n_1=n_2[/tex]
And in terms of volume and concentration:
[tex]C_1V_1=C_2V_2[/tex]
Thus, we can solve for the volume of the concentrated HCl as shown below:
[tex]V_1=\frac{C_2V_2}{C_1}[/tex]
Therefore, we plug in the data to get:
[tex]V_1=\frac{0.250M*0.500L}{1.75 M}\\\\V_1=0.0714L[/tex]
Best regards!
Calculate the mass, in grams, of 0.540 mol of manganese (Mn).
Report your answer with three significant figures.
Answer:
m = 29.6 grams
Explanation:
Given that,
Number of moles = 0.540
The molar mass of manganese = 54.93 g/mol
We know that,
Number of moles = given mass/molar mass
[tex]m=n\times M\\\\m=0.540 \times 54.93\\\\m=29.6\ g[/tex]
So, the required mass of the Manganese is equal to 29.6 grams.
? I JUST DONT UNDERSTAND
Answer:
5SiO2 + 2CaC2 → 5Si + 2CaO + 4CO2
Explanation:
When you are balancing an equation, you use coefficients to change the number of atoms of each type that are on each side of the equation.
You cannot change subscripts, the small numbers to the right of the substances. You can only add coefficients, the large numbers to the left of substances.
A balanced equation has the same number and type of atoms on both sides of the equation (the reactants on the left, the products on the right).
To begin, this equation has:
1 Si
2 O
1 Ca
2 C
on the left and
1 Si
1 Ca
3 O
1 C
on the right. Those numbers don't match!
By adding coefficients we end up with 5 Si, 10 O, 2 Ca and 4 C on both sides.
Determine if the following two structures are
identical, isomers, or unrelated?
A
B
С
identical
isomers
unrelated
Answer:
its C
Explanation:
The skeletal structure shows the outline of the compound with lines and bonds. Both the structures are unrelated. Thus, option C is correct.
What are isomers?Isomers are structures with identical molecular structures but differ in the skeletal or molecular representation. They also have varied properties as compared to the parent structure.
Identical compounds are structures that have the same atoms and are arranged with the same spatial design and orientation. The number of atoms and the spatial arrangement of the two compounds is different.
Therefore, the two compounds are unrelated.
Learn more about isomers here:
https://brainly.com/question/26658261
#SPJ2
State the coefficient required to correctly balance the following chemical equation:
__KCI + __Fe —-> __FeCI2+ __K
Answer:
2KCl+Fe---->FeCl2+2K
Explanation:
You can observe that the no.of atoms in reactant side is equal to that of products side of each element.
oil has a density of 8.5kg/L. what is the volume of 5.4kg oil
Answer:
0.64 L
Explanation:
Step 1: Given data
Density of oil (ρ): 8.5 kg/LMass of oil (m): 5.4 kgVolume of oil (V): ?Step 2: Calculate the volume corresponding to 5.4 kg of oil
Density is an intrinsic property and it is equal to the quotient between the mass and the volume.
ρ = m/V
V = m/ρ
V = 5.4 kg/(8.5 kg/L) = 0.64 L
How many atoms are in 90.43 moles of copper
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 8.12×10²³ atoms are in 90.43 mole of copper.
What is mole?
The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity of amount of substance. It measure the number of elementary entities of a given substance that are present in a given sample. There are so many formula for calculating mole.
we know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number
number of atoms/molecules=number of moles × 6.022×10²³(Avogadro number)
number of moles of copper=90.43 moles
Substituting all the given values in the above equation, we get
number of atoms/molecules= 90.43 × 6.022×10²³
number of atoms/molecules=8.12×10²³ molecules
Therefore, 8.12×10²³ atoms are in 90.43 mole of copper.
To know more about mole, here:
https://brainly.com/question/15209553
#SPJ2
Does the magnetic field lines of repelling magnets always combine. True or False?
Answer:
True
Explanation:
yes magnetic feild lines is always combined
A vitamin C (ascorbic acid) tablet was dissolved in approximately 50 mL of distilled water and titrated with the standardized NaOH solution. From the results of this titration, the mg of ascorbic acid in the tablet was calculated. Molecular formula of ascorbic acid: C6H8O6 Volume of NaOH required to neutralize ascorbic acid in Vitamin C tablet (mL) 20.74 Concentration of NaOH in mol/L, 0.201 Calculate the amount of ascorbic acid in the Vitamin C tablet in (mg).
Answer:
The correct answer is - 733.69 mg.
Explanation:
given:
The volume of ascorbic acid = 50 ml
The volume of NaOH = 20.74 ml
Molarity of NaOH = 0.201 M
formula = C6H8O6
Solution:
moles of NaOH for titration = molarity of NaOH × The volume of NaOH
= 0.201 × 20.74 × 10^-3
=4.16874 × 10^-3
then molecular weight of ascorbic acid
= 6 × 12+ 8×1+ 6× 16
=176g/mol
the molecular mass would be
= 4.16874 × 10^-3 × 176
= 733.69 × 10^-3 g
=733.69 mg
What will happen if HI is removed from a reaction vessel containing this
reaction at equilibrium?
H2+ 12 22H1
A. The reaction will slow down.
B. There will be no effect.
C. The rate of the forward reaction will increase.
D. The rate of the backward reaction will increase.
SUBMIT
Answer:
C I think
Explanation:
There will be no effect if HI is removed from a reaction vessel containing this reaction at equilibrium. When HI remove, concentration of all three component is change and reach a new equilibrium stage.
H2 + I2 ⇄ 2HI
So, B is correct option.
What is equilibrium?The stage in reversible reaction at which rate of forward reaction is equal to rate of backward reaction is equal is called an equilibrium.
To learn more about equilibrium here.
https://brainly.com/question/11420477
#SPJ2
Draw the structure formula for
1-ethyl-2,3-dimethylbenzene
Please help me
Answer:
Please see the attached picture.
Explanation:
1) Draw a benzene ring
2) On the first carbon, add a CH₂CH₃ (known as ethyl) since its location number is 1.
3) 'Dimethyl' refers to 2 methyl (CH₃) branches. The location numbers are 2 and 3, thus add a CH₃ on the 2nd and 3rd carbons.
4. What is the specific heat of a substance if 5800 joules is
released in a 250 gram sample that will cool the substance from
60 degrees to 45 degrees?
Answer: 23.2
Explanation:
The equation below illustrates the process of
Pb2+ (aq) + 11- (aq) → Pblu (s)
a) dissolution
b) precipitation
c) decomposition
Answer:
The correct answer is - b) precipitation.
Explanation:
In the given question the lead ion in an aqueous solution is mixed with the Leutium ion in an aqueous solution and forms an insoluble or solid salt. This type of reaction is referred to as precipitation reactions in chemistry.
Such reactions are helpful in determining if a particular ion is present in the solution or not.
Pb2+ (aq) + lu- (aq) → Pblu (s)
hi!! can somebody help me with this question?
which is the best example of commensalism?
A. honey bees feed on the pollen of cornflowers and help the flowers reproduce
B. barnacles ride on a gray whales back to obtain food, and the whale is not harmed
C. squirrels and chipmunks eat the same nuts in a forest where food is scarce
D. prairie dogs often collect and eat food in groups so they are better protected from enemies
thx to anybody that helps! ♡︎
Answer:
B: Barnacles ride on a gray whale's back to obtain food, and the hale is not harmed.
Explanation:
I got it right on Edge.
The nucleus of an atom stays together only because the repulsive forces, called
forces, are overcome by
even stronger attractive forces.
fusion
nuclear
electrostatic
Answer:
Electrostatic
Explanation:
The forces that are overcome are the repulsive electrostatic forces between the protons (all charged positively).
Do you think humans are responsible for global warming trends? Why or why not?
Answer:
Yes. At least some. There has been ups and downs in temperature ever since the Earth was created, and this is just another up in temperature. I do think that humans have made it worse though, with all of the greenhouse gases and things like that.