Ask question

Ask question

All categories

3 years ago

7

a mixture is made up of 3.35g of SiO2, 0.38g of cellulose and 8.76g of calcium carbonate. What is the percent of cellulose in th

e sample?

1 answer:

Alchen [17]3 years ago

6 0

Solution:

mass of the cellulose in the mixture is 0.38g

total mass of the mixture is:

3.35+0.38+8.76

=12.4g

thus the percentage of the cellulose in the mixture is:

mass of the cellulose/total mass of the mixture*100%

0.38/12.4*100%

=3%

You might be interested in

How many miles can you drive, if your car gets 21.3 miles per gallon and you have 12.0 gallons of gas?

Travka [436]

Answer:

255.6

Explanation:

If you have 12 gallons and get 21.3mpg,

-Multiply 21.3 by 12

-you can travel 255.6 miles before running out of gas.

-If you need to estimate, round up to 256 miles.

6 0

3 years ago

How many grams of KBr is required to prepare 100 mL of<br> 2.0 M KBr solution?

sesenic [268]

Answer:

23.8g

Explanation :

Convert 2.0M into mol using mol= concentration x volume

2.0M x 0.1L (convert 100mL to L since the units for M is mol/L)

= 0.2 mol

We can now find grams by using the molar mass of KBr

=119.023 g/mol (Found online) webqc.org

but can be be calculated by using the molecular weight of K and Br found on the periodic table

We can now calculate the grams by using grams=mol x molar mass

119.023g/mol x 0.2mol

= 23.8046 g

=23.8g (rounded to 1decimal place)

4 0

2 years ago

If a mixture of two metals was separated based on one metal's ability to be drawn into a thin wire, which property listed below

IrinaK [193]

Ductility because ductility is the ability to be stretched and be made into wires.

6 0

3 years ago

10. Which of the following best describes the reaction 2VO3– (aq) + Zn (s) + 8H+ (aq) → 2VO2 (aq) + Zn2+ (aq) + 4H2O (l)? ______

Oduvanchick [21]

Correct answer is option E. <span>It is a redox reaction in which Zn is oxidized at the anode, and V is reduced at the cathode.

Reason:
In above reaction, the oxidation state of VO3- is +5, while that of VO2 is +4. Thus there is reduction of V from +5 to +4
In case of Zn, oxidation state of Zn is increased from 0 to +2, Thus process is referred as oxidation. </span>

3 0

2 years ago

For the reaction 2 H2S(g) D 2 H2 (g) + S2 (g), Kp = 1.5 × 10−5 at 800.0°C. If the initial partial pressures of H2 and S2 in a cl

Usimov [2.4K]

Answer: The approximate equilibrium partial pressure of $H_2S$ is 3.92 atm

Explanation:

Equilibrium constant is the ratio of the concentration of products to the concentration of reactants each term raised to its stochiometric coefficients.

The given balanced equilibrium reaction is,

$2H_2S(g)\rightleftharpoons 2H_2(g)+S_2(g)$

$K_p=\frac{[H_2]^2\times [S_2]}{[H_2S]^2}$

$1.5\times 10^{-5}=\frac{[H_2]^2\times [S_2]}{[H_2S]^2}$

On reversing the reaction:

$2H_2(g)+S_2(g)\rightleftharpoons 2H_2S(g)$

initial pressure 4.00atm 2.00 atm 0

eqm (4.00-2x)atm (2.00-x) atm 2x atm

$K_p=\frac{[H_2S]^2}{[H_2]^2\times [S_2]}$

$K_p'=\frac{1}{K_p}=0.67\times 10^5$

$2H_2(g)+S_2(g)\rightleftharpoons 2H_2S(g)$

$0.67\times 10^5=\frac{2x]^2}{[4.00-2x]^2\times [2.00-x]}$

$x=1.96$

$[H_2S]=2x=2\times 1.96=3.92 atm$

Thus approximate equilibrium partial pressure of $H_2S$ is 3.92 atm

3 0

3 years ago