All categories

2 years ago

4. Convert the following: a. 4g mol of MgCl2 to g b. 2 lb mol of C3H8 to g c. 16 g of N2 to lb mol d. 3 lb of C2H6O to g mol

Chemistry

1 answer:

Nuetrik [128]2 years ago

6 0

Answer:

a) 381.2 g

b) 39916 g

c) 0.0013 lb mol

d) 29.6 g mol

Explanation:

The molecular weight (mw) of a compound is the mass of it per mole, so it's the ratio of the mass (m) per mole (n).

a) The molecular weight of one mol is found at the periodic table. So, for Mg, mw = 24.3 g/mol, for Cl = 35.5 g/mol, so for MgCl2, mw = 24.3 + 2*35.5 = 95.3 g/mol. The g mol is the mass divided by the molecular weight:

g mol = m/mw

4 = m/95.3

m = 381.2 g

b) The pound (lb) is a unity of mass, and the lb mol is a unity of the mass divided by the molecular weight. So, by the periodic table, the molecular weight of C3H8 is 3*12 (of C) + 8*1 (of H) = 44 lb/mol.

lb mol = m/mw

2 = m/44

m = 88 lb

1 lb = 453.592 g

So, m = 88*453.592 = 39916 g

c) The molecular weight of N2 is 2*14 (of N) = 28 lb/mol.

m = 16/453.592 = 0.0353 lb

lb mol = m/mw

lb mol = 0.0353/28

lb mol = 0.0013 lb mol

d) The molecular weight is 2*12 (of C) + 6*1(of H) + 1*16(of O) = 46 g/mol

3 lb = 1360.78 g

g mol = m/mw

g mol = 1360.78/46

g mol = 29.6 g mol

You might be interested in

The bomb calorimeter in Exercise 102 is filled with 987g water. The initial temperature of the calorimeter contents is 23.32. A

Sholpan [36]

Answer:

25.907°C

Explanation:

In Exercise 102, heat capacity of bomb calorimeter is 6.660 kJ/°C

The heat of combustion of benzoic acid is equivalent to the total heat energy released to the bomb calorimeter and water in the calorimeter.

Thus:

$-q_{combust} = q_{water} + q_{calori}$

$q_{combust}$ = heat of combustion of benzoic acid

$q_{water}$ = heat energy released to water

$q_{calori}$ = heat energy released to the calorimeter

Therefore,

$-m_{combust}*H_{combust} = [m_{water}*c_{water} + C_{calori}]*(T_{f} - T_{i})$

1.056*26.42 = [0.987*4.18 + 6.66]( $T_{f}$ - 23.32)

27.8995 = [4.12566+6.660]( $T_{f}$ - 23.32)

( $T_{f}$ - 23.32) = 27.8995/10.7857 = 2.587

$T_{f}$ = 23.32 + 2.587 = 25.907°C

4 0

3 years ago

What are the pH of these solutions?

Tju [1.3M]

Answer:

The answer to your question is below

Explanation:

a) HCl 0.01 M

pH = -log [0.01]

pH = - (-2)

pH = 2

b) HCl = 0.001 M

pH = -log[0.001]

pH = -(-3)

pH = 3

c) HCl = 0.00001 M

pH = -log[0.00001]

pH = - (-5)

pH = 5

d) Distilled water

pH = 7.0

e) NaOH = 0.00001 M

pOH = -log [0.00001]

pOH = -(-5)

pH = 14 - 5

pH = 9

f) NaOH = 0.001 M

pOH =- log [0.001]

pOH = 3

pH = 14 - 3

pH = 11

g) NaOH = 0.1 M

pOH = -log[0.1]

pOH = 1

pH = 14 - 1

pH = 13

3 0

2 years ago

What is the expected mass (in kg) of a 10 over 5 B isotope? 1 proton = 1.6726 × 10-27 kg 1 neutron = 1.6749 × 10-27 kg A.1.67 ×

Ira Lisetskai [31]

$^{10}_5 B$
An atom of this isotope contains 5 protons and 10-5=5 neutrons.

$5 \times 1.6726 \times 10^{-27} + 5 \times 1.6749 \times 10^{-27} = \\
8.363 \times 10^{-27} + 8.3745 \times 10^{-27}= \\
16.7375 \times 10^{-27}= \\
1.67375 \times 10^{-26} \approx \\
1.67 \times 10^{-26}$

The answer is A. 1.67 × 10⁻²⁶ kg.

8 0

3 years ago

Explain how our body systems work together to get oxygen into and around our body.

aleksandrvk [35]

Answer: (1) Inhales (breathes in) Oxygen - good for the body - gives it to the Circulatory System to be transported throughout the body through the blood. (1) Digestive System gets nutrients (good) from food and hands it over to the blood and Circulatory System then carries those nutrients where they need to go.

7 0

2 years ago

Name an element in the third period (row) of the periodic table with a total of 4 3p electrons

Wittaler [7]

Answer:

sulfur

Explanation:

sulfur has 4p electrons.

phosphorus has 3p electrons.

The question is asking which one has 4

3 0

2 years ago