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3 years ago

145.8g of Mg contains how many moles?

Chemistry

1 answer:

Tems11 [23]3 years ago

8 0

A: 6 moles
You have to find the molar mass and then multiply

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1. What is a food web?

Anuta_ua [19.1K]

Answer:

a producer and consumer relationship how several food chains and related.

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2 years ago

Read 2 more answers

The powder mixture (Cu, Al and Fe) = 10g was oxidized from sufficient chloride acid. 1) What are the possible reactions to the p

Mandarinka [93]

Answer:

1) 2Al + 6HCl ⟶ 2AlCl₃ + 3H₂

Fe + 2HCl ⟶ FeCl₂ + H₂

2) Cu = 2.5 g; Al = 3.5 g; Fe = 4.0 g

Explanation:

1) Possible reactions

2Al + 6HCl ⟶ 2AlCl₃ + 3H₂

Fe + 2HCl ⟶ FeCl₂ + H₂

2) Mass of each metal

a) Mass of Cu

The waste was the unreacted copper.

Mass of Cu = 2.5 g

b) Masses of Al and Fe

We have two relations :

Mass of Al + mass of Fe = 10 g - 2.5 g = 7.5 g

H₂ from Al + H₂ from Fe = 6.38 L at NTP

i) Calculate the moles of H₂

NTP is 20 °C and 1 atm.

$\begin{array}{rcl}pV & = & n RT\\\text{1 atm} \times \text{6.38 L} & = & n \times 0.08206 \text{ L}\cdot\text{atm}\cdot\text{K}^{-1}\text{mol}^{-1} \times \text{293.15 K}\\6.38 & = & 24.06n \text{ mol}^{-1} \\n & = & \dfrac{6.38}{24.06 \text{ mol}^{-1} }\\\\ & = & \text{0.2652 mol}\\\end{array}$

(ii) Solve the relationship

Let x = mass of Al. Then

7.5 - x = mass of Fe

Moles of Al = x/27

Moles of Fe = (7.5 - x)/56

Moles of H₂ from Al = (3/2) × Moles of Al = (3/2) × (x/27) = x /18

Moles of H₂ from Fe = (1/1) × Moles of Fe = (7.5 - x)/56

∴ x/18 + (7.5 - x)/56 = 0.2652

56x + 18(7.5 - x) = 267.3

56x + 135 - 18x = 267.3

38x = 132.3

x = 3.5 g

Mass of Al = 3.5 g

Mass of Fe = 7.5 g - 3.5 g = 4.0 g

The masses of the metals are Cu = 2.5 g; Al = 3.5 g; Fe = 4.0 g

4 0

3 years ago

What are the lanthanide & actinide series?

ch4aika [34]

Answer:

The lanthanides and actinides together are sometimes called the inner transition elements.

Explanation:

They are called this because they come up in the periodic table after actinium

Hope this helps :)

8 0

2 years ago

The compound trimethylamine, (CH3)3N, is a weak base when dissolved in water. Write the Kb expression for the weak base equilibr

Rina8888 [55]

<u>Answer:</u> The expression of $K_b$ is written below.

<u>Explanation:</u>

We are given a chemical compound which is trimethylamine that acts as a weak base when dissolved in water.

It accepts a proton from the water to form trimethylammonium ion and hydroxide ion.

The chemical equation for the reaction of trimethylamine in water follows:

$(CH_3)_3N+H_2O\rightleftharpoons (CH_3)_3NH^++OH^-$

The expression of $K_b$ for above equation follows:

$K_b=\frac{[(CH_3)_3NH^+][OH^-]}{[(CH_3)_3N]}$

Hence, the expression of $K_b$ is written above.

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3 years ago

What is the percent of N in

Pie

Answer:

8.24

Explanation:

the answer is explained above

7 0

3 years ago