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3 years ago

Which task most likely involves a calculation that uses moles?

Chemistry

2 answers:

luda_lava [24]3 years ago

8 0

Answer:

determining the number of atoms in a jar of liquid

Explanation:

In determining the number of atoms that makes up a substance, the number of moles is very essential.

The mole is the convenient unit of quantity of particles. It can be likened to a quantity of things in everyday life like a dozen, a score and a gross.

A mole of any substance contains 6.02 x 10²³ particles
These particles can be atoms, protons, neutrons, electrons etc.

So, to find the number of atoms, we must know the number of moles.

Alenkinab [10]3 years ago

7 0

Answer:

3rd choice

Explanation:

I got it correct

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What volume of 3.00 MM HClHCl in liters is needed to react completely (with nothing left over) with 0.750 LL of 0.500 MM Na2CO3N

AlladinOne [14]

Answer: The volume of HCl needed is 0.250 L

Explanation:

To calculate the number of moles for given molarity, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}$

For sodium carbonate:

Molarity of sodium carbonate solution = 0.500 M

Volume of solution = 0.750 L

Putting values in above equation, we get:

$0.500M=\frac{\text{Moles of sodium carbonate}}{0.750}\\\\\text{Moles of sodium carbonate}=(0.500mol/L\times 0.750L)=0.375mol$

The chemical equation for the reaction of sodium carbonate and HCl follows:

$Na_2CO_3+2HCl\rightarrow 2NaCl+H_2CO_3$

By Stoichiometry of the reaction:

1 mole of sodium carbonate reacts with 2 moles of HCl

So, 0.375 moles of sodium carbonate will react with = $\frac{2}{1}\times 0.375=0.750mol$ of HCl

Now, calculating the volume of HCl by using equation 1:

Moles of HCl = 0.750 moles

Molarity of HCl = 3.00 M

Putting values in equation 1, we get:

$3.00M=\frac{0.750mol}{\text{Volume of solution}}\\\\\text{Volume of solution}=\frac{0.750mol}{3.00mol/L}=0.250L$

Hence, the volume of HCl needed is 0.250 L

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3 years ago

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Tanzania [10]

Answer:

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Explanation:

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levacccp [35]

Answer:

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Explanation:

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3 years ago

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Anna007 [38]

Answer:

This question is incomplete

Explanation:

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From the question, the 50 mL beaker will provide a "more accurate" measurement of the volume of the bromine than the 100 mL beaker if the 50 mL beaker can contain all the sample of bromine water provided.

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mars1129 [50]

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4 years ago