(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

How do I find theDensityof X (Part A) and how do I find theConcentrationof X in a solution (Part B)?

Part A:

I have 4mL of X. The mass of 4mL of X is 10g. Calculate the density of X.

Part B:

I have 7g of X in 100mL of Water. Calculate the concentration of X.

The FINAL ANSWER must be written in BOTH "g/L" and as a percent (%).

2. Relevant equations

Density of X = Mass/Volume

Concentration of X = grams of solute/Litre of solution

3. The attempt at a solution

What did I do:

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Part A:

I have 4mL of X. The mass of 4mL of X is 10g. Calculate the density.

Finding Density of X:

I have 10g of X. (10g is the mass)

I have 4mL of X. (I'm thinking that 4mL is the volume)

Density of X = Mass/Volume

Density of X = 10/4

Density of X = 2.5g/mL

Therefore, the density of X is 2.5g/mL.

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Part B:

I have 7g of X in 100mL of Water. Calculate the concentration of X.

Finding Concentration of X:

I have 7g. (grams of solute)

I have 100mL of Water, which is 0.100L. (Solution in L)

Concentration of X = grams of solute/Litre of solution

[X] = 7/0.100

[X] = 70g/L

As a percentage:

70g/L = 70/1000 = 0.07 = 7%

Therefore, the concentration of 7g of X in 100mL of Water is 70g/L (7%).

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Thoughts:

You know how I calculated the density of X in Part A (2.5g/mL), don't I use that information to calculate the concentration of X in Part B?

Does the density of the solute matter when calculating the concentration of X? If so, how do I use 2.5g/mL (density of X) in order to calculate the concentration of X in 100mL of Water?

I hope you are able to help me.

Thank you!

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# Homework Help: Finding the concentration of X

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