Help please!! I thought it was 374.8 but it keeps saying to check my significant digits

For the reaction of deprotonation of formic acid, the concentration of HCOO⁻ at equilibrium is 0.0151 M if the initial concentration of formic acid is 1.35 M.  

The reaction of deprotonation of formic acid is the following:

CHOOH + H₂O ⇄ HCOO⁻ + H₃O⁺

At the equilibrium we have:

CHOOH + H₂O ⇄ HCOO⁻ + H₃O⁺    (1)

1.35 - x                         x           x

The acid equilibrium constant for this reaction is:

[tex] K_{a} = \frac{[HCOO^{-}][H_{3}O^{+}]}{[CHOOH]} = 1.7 \cdot 10^{-4} [/tex]  (2)

Entering the values of [CHOOH] = 1.35-x, [HCOO⁻] = [H₃O⁺] = x, into equation (2) we have:

[tex] 1.7 \cdot 10^{-4} = \frac{[HCOO^{-}][H_{3}O^{+}]}{[CHOOH]} = \frac{x^{2}}{(1.35 - x)} [/tex]  

[tex]1.7 \cdot 10^{-4}(1.35 - x) - x^{2} = 0[/tex]

After solving the above quadratic equation and taking the positive value for x (concentrations cannot be negative), we have:

[tex] x = [HCOO^{-}] = [H_{3}O^{+}] = 0.0151 M [/tex]

Therefore, the concentration of HCOO⁻ at equilibrium is 0.0151 M.

Learn more about the equilibrium constant here:

I hope it helps you!

Answer:

J

Explanation:

Because the vapor can be turned back to water and the vapor is still considered water.

Answer:

molecular compound

Explanation:

it has two or more nonmetal elements and are covalently bonded

If an element has three valence electrons, it is most likely a metal.

In the periodic table, metals are found towards the left hand side of the table. Metals have fewer valence electrons than nonmetals. In the periodic table, there are more metallic than nonmetallic elements.

Metals of group 13 typically have three valence electrons. Hence, if an element has three valence electrons, it is most likely a metal of group 13.

Learn more: https://brainly.com/question/5624100

Answer:

Answer: 3 significant figures

Explanation: because in scientific notation only the before and after decimal number are considered but in standard form all numbers including exponents are all significant figures

Answer:

3 significant figures

Explanation:

0's are not significant.

I hope it helps you!

[tex]GraceRosalia[/tex]

Answer:

30 protons

Explanation: Each zinc isotope contains 30 protons, 30 massive, positively charged nuclear particles

30 protons, 34 neutrons, and 30 electrons.

Answer:

An isotope is one of two or more forms of the same chemical element. Different isotopes of an element have the same number of protons in the nucleus, giving them the same atomic number, but a different number of neutrons giving each elemental isotope a different atomic weight.

Explanation:

I hope you have a nice day and please mark me(:

Answer: Elements are simply what you see on the periodic table. E.g. carbon, oxygen, hydrogen etc. Isotopes are elements with different masses. ... So isotopes have the same amount of protons but with different amounts of neutrons.

Explanation: plz mark brainliest!

Explanation:

Answer:

D. Grass Health

Explanation:

v=5.0×10^12Hz

[tex]\\ \sf\longmapsto E=hv[/tex]

[tex]\\ \sf\longmapsto E=6.626\times 10^{-34}Js\times 5\times 10^12s^{-1}[/tex]

[tex]\\ \sf\longmapsto E=33.13\times 10^{-22}J[/tex]

The penalty for not voting in New South Wales is a $55 fine. You must respond within 28 days of the issue date of the notice. You will have four options: If you voted, you can provide details of where and when using our non-voter self-service portal.

Answer: 49,603.4011

Explanation:

Answer:

49603.4011

Explanation:

89.001

+. 0.0001

348.4

49166

answer: 49603.4011

Answer:

A a chemical change

Explanation:

because a chemical change is when you mix tow substance together and they creat a new substance

Answer:

nucleosynthesis

Explanation:

The correct answer is nucleosynthesis.

After the hydrogen in the star's core is exhausted, the star can fuse helium to form progressively heavier elements, carbon and oxygen, and so on, until iron and nickel are formed. Up to this point, the fusion process releases energy. The formation of elements heavier than iron and nickel requires an input of energy.

In a supernova explosion, neutron capture reactions take place (this is not fusion), leading to the formation of heavy elements. This is the reason why it is said that most of the stuff that we see around us comes from stars and supernovae (the heavy elements part).

Learn more about nucleosynthesis here https://brainly.com/question/20767918

#SPJ2

Explanation:

3 moles of O2 will be produced from 2moles of NaCLO3.

hope this helps you.

Answer:

0.4699

Explanation:

There are 300 light particles in an airtight container. The adjustment that would increase the speed of the particle is keeping the pressure constant and increasing the temperature. Option B is correct.

The speed of a particle is the distance traveled by one molecule of a substance. Particles travel as a result of the kinetic energy they possess.

The kinetic energy attributed to each particle rises as the temperature rises.

As a result, in 300 light particles, the particles will travel more quickly when the temperature is increased while the pressure of the particle remains constant.

Therefore, we can conclude that the adjustment that would increase the speed of the particles is keeping the pressure constant and increasing the temperature.

Learn more about particles here:

https://brainly.com/question/2288334?referrer=searchResults

Answer:

2 electrons

8 electrons

8 electrons

1 electron (just count in the rings for these ones)

19 protons (it says "P=19" in the middle. The P stands for Protons)

K (it's from Latin medieval Latin "kalium")

39 (add proton and neutron amounts to get the approximate atomic mass--electrons are negligible)

Explanation:

Answer:

it does not have a control group

Under conditions of very high pressures, the volume would be lower than predicted by the Ideal Gas Law.

According to the kinetic theory of gases, a gas spreads out to fill the volume of the container holding it. Hence a gas does not have a definite volume due to the fact that there is no inter-molecular interaction between gas molecules.

When the gas is subjected to very high pressure, inter-molecular interactions become significant leading to a decrease in the volume of the gas.

Therefore, when subjected to high pressure, the experimental volume would be lower than predicted by the Ideal Gas Law.

Learn more: https://brainly.com/question/21443108

There are 2.72 kilograms of nitrogen present in a 3.50 L sample of N₂O.

To find the mass of nitrogen in N₂O, we must calculate the number of moles of N₂O.  

[tex] n_{N_{2}O} = \frac{m_{N_{2}O}}{M{N_{2}O}} [/tex]  (1)

Where:

[tex] m_{N_{2}O}[/tex]: is the mass of N₂O

[tex]M_{N_{2}O}[/tex]: is the molar mass of N₂O = 44.013 g/mol

The mass of N₂O can be founded from the density:

[tex] d = \frac{m}{V} [/tex] (2)

Where:

d: is the density of N₂O = 1.22 g/mL

V: is the volume = 3.50 L = 3500 mL

Then, the mass of N₂O is (eq 2):

[tex] m = d*V = 1.22 g/mL*3500 mL = 4270 g [/tex]

Now, the number of moles of N₂O is (eq 1):

[tex] n_{N_{2}O} = \frac{4270 g}{44.013 g/mol} = 97.02 \:moles [/tex]

Knowing that in 1 mol of N₂O we have 2 moles of N, the number of moles of nitrogen is:

[tex] n_{N} = \frac{2\: moles \: N}{1 \:mol \: N_{2}O}*n_{N_{2}O} = \frac{2\: moles \: N}{1 \:mol \: N_{2}O}*97.02 \:moles \:N_{2}O = 194.04 \: moles [/tex]

Finally, with the number of moles of N we can find its mass:

[tex] m = n_{N}*M_{N} = 194.04 \:moles*14.007 g/mol = 2717.9 g = 2.72 kg [/tex]

Therefore, there are 2.72 kilograms of nitrogen.  

Find more about the number of moles here:

https://brainly.com/question/10165629?referrer=searchResults  

I hope it helps you!

Answer:

nCl= 0,062x3/2=0,093(mol)

Explanation:

Answer:

I think it's number one option

Answer:

Ionic compounds conduct electricity when molten or in aqueous solution, because their ions are free to move from place to place. Ionic compounds cannot conduct electricity when solid, as their ions are held in fixed positions and cannot move.

Explanation:

Pls mark me as the brainlest!!,