All categories

3 years ago

PLEASE ANSWER QUICK

Chemistry

1 answer:

zubka84 [21]3 years ago

3 0

The equation to find the percentage by mass of a solution is:

(Mass of solute/mass of solution) x 100 = percentage by mass

So, let's identify the variables.

Mass of solute: 22g

Mass of solution: 112g

The reason that the solution is 112g and not 90g is because the solution needs to include the mass of the solute and solvent, meaning 90 + 22 is the mass of the solution.

(22/112) x 100 = 19.6%

You might be interested in

How many grams of XeF6 are required to react with 0.579 L of hydrogen gas at 6.46 atm and 45°C in the reaction shown below?

ankoles [38]

The chemical reaction equation for this is

XeF6 + 3H2 ---> Xe + 6HF

Assuming gas behaves ideally, we use the ideal gas formula to solve for number of moles H2 with T = 318.15K (45C), P = 6.46 atm, V = 0.579L. Then we use the gas constant R = 0.08206 L atm K-1 mol-1.

we get n = 0.1433 moles H2

to get the mass of XeF6,

we divide 0.1433 moles H2 by 3 since 1 mole XeF6 needs 3 moles H2 to react then multiply by the molecular weight of XeF6 which is 245.28 g/mole XeF6.

0.1433 moles H2 x $\frac{1 mole XeF6}{3 moles H2}$ x $\frac{245.28 g XeF6}{1 mole XeF6}$ = 11.71 g XeF6

Therefore, 11.71 g of XeF6 is needed to completely react with 0.579 L of Hydrogen gas at 45 degrees Celcius and 6.46 atm.

3 0

3 years ago

1. Surface area, agitation, and ____ affect the dissolving rate of a solid. 1. termperature 2. location

mamaluj [8]

Answer:??

Explanation:

3 0

2 years ago

Read 2 more answers

If a substance has a half-life of 55.6 s, and if 230.0 g of the substance are present initially, how many grams will remain afte

Assoli18 [71]

Answer:

$m=0.127g$

Explanation:

Hello,

In this case, for a first-order reaction, we can firstly compute the rate constant from the given half-life:

$k=\frac{ln(2)}{t_{1/2}} =\frac{ln(2)}{55.6s}=0.0125s^{-1}$

In such a way, the integrated first-order law, allows us to compute the final mass of the substance once 10.0 minutes (600 seconds) have passed:

$m=m_0*exp(-kt)=230.0g*exp(-0.0125s^{-1}*600s)\\\\m=0.127g$

Best regards.

6 0

3 years ago

The electron affinity of an element is positive if energy is absorbed during the process of accepting an electron and negative i

julsineya [31]

Answer:

See explanation

Explanation:

Electron affinity is the energy released when an extra electron is added to a neutral gaseous atom. A negative value of electron affinity indicates that energy is given out and vice versa.

Metals have positive electron affinity since electrons rarely accept electrons, so;

Na(g)+ 1e^- → Na^-(g) positive

Mg(g)+1e^- → Mg^-(g) positive

For the last case; Br(g)+ 1e^- → Br^-(g), the electron affinity for the non-metals is negative. hence the answer

5 0

3 years ago

What is the mass of the ethanol that exactly fills a 200.0 mL container? The density of ethanol is 0.8 g/mL. please help

Naddik [55]

160.0g

Mass =volume x density = 200.0 mL x 0.8 g/mL= 160.0 g

7 0

3 years ago