All categories

2 years ago

Calculate the amount, in moles, of each of the following. You may round atomic masses to one decimal place.

Chemistry

1 answer:

Vlada [557]2 years ago

7 0

Answer:

The answer to your question is:

a) 0.023 mol of CdS

b) 0.12 mol of MoO3

c) 7.3 mol of AlPO4

Explanation:

a) CdS

MW = 112.4 + 32

= 144 g

144g ------------------ 1 mol

3.28g -------------- x

x = (3.28 x 1) / 144

x = 0.023 mol

b) MoO3

MW = 96 + 3(16) = 144 g

144g ------------------- 1 mol

17.5g ----------------- x

x = (17.5 x 1) / 144

x = 0.12 mol

c) AlPO4

MW = 27 + 31 + 4(16)

MW = 122 g

122 g ------------------ 1mol

890 g ------------------ x

x = (890 x 1) / 122

x = 7.3 mol of AlPO4

You might be interested in

Fill in the blanks to determine the number of protons and electrons in an oxygen ion. (Consult the periodic table to determine t

Arte-miy333 [17]

The answer would be 2

6 0

3 years ago

Read 2 more answers

A 111.6 gram sample of iron (MW=55.8) was heated from 0 degrees C to 20 degrees C. It absorbed 1004 Joules of energy. What is th

qwelly [4]

Use the equation q=ncΔT.
q= heat absorbed our released (in this case 1004J)
n= number of moles of sample ( in this case 2.08 mol)
c=molar heat capacity
ΔT=change in temperature (in this case 20°C)
You have to rewrite the equation for c.
c=q/nΔT
c=1004J/(2.08mol x 20°C)
c=24.1 J/mol°C

I hope this helps

7 0

2 years ago

I have five less protons than the least massive metalloid in the fourth period. Who am I?

exis [7]

Answer:

You are the Cobalt

Explanation:

The least massive metalloid in the fourth period is Germanium, and it have 32 protons. If you have 5 less protons: 32 - 5 = 27 protons. The element with 27 protons is Cobalt

6 0

2 years ago

Is carbon dioxide a reactant

Harman [31]

Answer: No

Explanation: Reactants are the substances present at the beginning of a chemical reaction. In the burning of natural gas, for example, methane (CH4) and oxygen (O2) are the reactants in the chemical reaction. Products are the substances formed by a chemical reaction. In the burning of natural gas, carbon dioxide (CO2) and water (H2O) are the products formed by the reaction.

3 0

3 years ago

In a 0.730 M solution, a weak acid is 12.5% dissociated. Calculate Ka of the acid.

Mamont248 [21]

Answer:

Approximately $1.30 \times 10^{-2}$ , assuming that this acid is monoprotic.

Explanation:

Assume that this acid is monoprotic. Let $\rm HA$ denote this acid.

$\rm HA \rightleftharpoons H^{+} + A^{-}$ .

Initial concentration of $\rm HA$ without any dissociation:

$[{\rm HA}] = 0.730\; \rm mol \cdot L^{-1}$ .

After $12.5\%$ of that was dissociated, the concentration of both $\rm H^{+}$ and $\rm A^{-}$ (conjugate base of this acid) would become:

$12.5\% \times 0.730\; \rm mol \cdot L^{-1} = 0.09125\; \rm mol \cdot L^{-1}$ .

Concentration of $\rm HA$ in the solution after dissociation:

$(1 - 12.5\%) \times 0.730\; \rm mol \cdot L^{-1} = 0.63875\; \rm mol\cdot L^{-1}$ .

Let $[{\rm HA}]$ , $[{\rm H}^{+}]$ , and $[{\rm A}^{-}]$ denote the concentration (in $\rm mol \cdot L^{-1}$ or $\rm M$ ) of the corresponding species at equilibrium. Calculate the acid dissociation constant $K_{\rm a}$ for $\rm HA$ , under the assumption that this acid is monoprotic:

$\begin{aligned}K_{\rm a} &= \frac{[{\rm H}^{+}] \cdot [{\rm A}^{-}]}{[{\rm HA}]} \\ &= \frac{(0.09125\; \rm mol \cdot L^{-1}) \times (0.09125\; \rm mol \cdot L^{-1})}{0.63875\; \rm mol \cdot L^{-1}}\\[0.5em]&\approx 1.30 \times 10^{-2} \end{aligned}$ .

5 0

3 years ago