All categories

2 years ago

A solution was prepared by dissolving 31.0 g of kcl in 225 g of water. part a calculate the mass percent of kcl in the solution.

1 answer:

3 0

Answer: Mass % KCL: Add the grams of both compounds (31.0 g KCL + 225 g water) to find total mass and then divide the grams of KCL over the total mass, then multiply by 100: ( 31.0 g KCL / 31.0 g + 225 G) * 100% Mole fraction KCL Calculate the moles of KCL and water and add them to find the total moles (Moles of KCL + moles of water). Then, divide the number of KCL moles over the total moles. moles of KCL/ moles kcl + moles water= mole fraction of KCL

You might be interested in

What is the pH of the solution in which the [H+] is 1.0 × 10–4 mol/L ?

ddd [48]

PH is a simplified observation of the acidity of a solution, defined as the -log [H+] (negative logarithm of the hydrogen concentration).

-log[10^-4] = 4

The pH of this solution is 4.

5 0

2 years ago

Calculate the mass of chloroform that contains 1.00X10^12 molecules of chloroform

Brums [2.3K]

Molar mass of chloroform (CHCl3)
C = 1 * 12 = 12 a.m.u
H = 1 * 1 = 1 a.m.u
Cl = 3 * 35.5 = 106.5 a.m.u
Molar Mass (CHCl3) = 12 + 1 + 106.5 = 119.5 g / mol

Knowing that: The value of Avogadro's constant corresponds to approximately $6,02*10^{23}$ molecules, if chloroform contains $1,00 * 10^{12}$ molecules. 
We have:

 $1,00 * 10^{12} * 6,02 * 10^{23} = 6,02 * 10 ^ {35} molecules$ 

Now, how many grams are there in the chloroform molecule?

grams -------- molecules
119,5 → $6,02 * 10^{23}$
x → $6,02 * 10^{35}$

$6,02 * 10 ^ {23} * x = 119,5 * 6,02 * 10 ^{35}$
$6,02 * 10 ^ {23}x = 719,39 * 10^{35}$
$x = \frac{719,39}{6,02}*10^{35-23}$
$\boxed{x = 119,5*10^{12}grams}$

7 0

2 years ago

How test berween nitric and sulferic acid?

steposvetlana [31]

Ba(OH)₂(aq) + 2HNO₃(aq) = Ba(NO₃)₂(aq) + 2H₂O(l)
At the reaction of barium hydroxide with nitric acid there are no visual changes.

Ba(OH)₂(aq) + H₂SO₄(aq) = BaSO₄(s) + 2H₂O
At the reaction of barium hydroxide with sulfuric acid the precipitat of white color is formed.

7 0

2 years ago

Question 3

harina [27]

Answer: 0.118M

Explanation:

The formula for molarity is: $M=\frac{mol solute}{L solution}$

First, we need to find the number of moles of NaCl.

$2.70gNaCl*\frac{1molNaCl}{58.44gNaCl} =0.05molNaCl$

Next, we must convert millimeters to liters. We can do that by dividing the number of mL by 1000.

$\frac{425mL}{1000} =0.425L$

Now we have our needed data! All we need to do now is plug in our data to the molarity formula.

$M=\frac{0.05mol}{0.425L} =0.118M$

I hope this helps! Pls mark brainliest!! :)

4 0

1 year ago

Do you think it is appropriate to have diet pop available in your school?

pashok25 [27]

Answer:

I think so

Explanation:

It would provide an extra energy boost with lower sugars. Students bring drinks to school anyways so it would be nice to offer some that aren't as detrimental.

3 0

2 years ago