What is the number of valence electrons in a calcium atom? * 8 2 18 20

Medicinal “ether" is produced when ethyl alcohol is treated with an acid. How many grams of

DochEvi [55]

Answer:

34.3 g

Explanation:

Step 1: Write the balanced equation

2 CH₃CH₂OH ⇒ CH₃CH₂OCH₂CH₃ + H₂O

Step 2: Calculate the moles corresponding to 50.0 g of CH₃CH₂OH

The molar mass of CH₃CH₂OH is 46.07 g/mol.

50.0 g × 1 mol/46.07 g = 1.09 mol

Step 3: Calculate the theoretical moles of CH₃CH₂OCH₂CH₃ produced

The molar ratio of CH₃CH₂OH to CH₃CH₂OCH₂CH₃ is 2:1. The moles of CH₃CH₂OCH₂CH₃ theoretically produced are 1/2 × 1.09 mol = 0.545 mol.

Step 4: Calculate the real moles of CH₃CH₂OCH₂CH₃ produced

The percent yield of the reaction is 85%.

0.545 mol × 85% = 0.463 mol

Step 5: Calculate the mass corresponding to 0.463 moles of CH₃CH₂OCH₂CH₃

The molar mass of CH₃CH₂OCH₂CH₃ is 74.12 g/mol.

0.463 mol × 74.12 g/mol = 34.3 g

6 0

3 years ago

A gaseous mixture composed of 20% CH4, 30% C2H4, 35% C2H2, and 15% C2H20. What is the average molecular weight of the mixture? a

Semenov [28]

<u>Answer:</u> The correct answer is Option d.

<u>Explanation:</u>

We are given:

Mass percentage of $CH_4$ = 20 %

So, mole fraction of $CH_4$ = 0.2

Mass percentage of $C_2H_4$ = 30 %

So, mole fraction of $C_2H_4$ = 0.3

Mass percentage of $C_2H_2$ = 35 %

So, mole fraction of $C_2H_2$ = 0.35

Mass percentage of $C_2H_2O$ = 15 %

So, mole fraction of $C_2H_2O$ = 0.15

We know that:

Molar mass of $CH_4$ = 16 g/mol

Molar mass of $C_2H_4$ = 28 g/mol

Molar mass of $C_2H_2$ = 26 g/mol

Molar mass of $C_2H_2O$ = 48 g/mol

To calculate the average molecular mass of the mixture, we use the equation:

$\text{Average molecular weight of mixture}=\frac{_{i=1}^n\sum{\chi_im_i}}{n_i}$

where,

$\chi_i$ = mole fractions of i-th species

$m_i$ = molar masses of i-th species

$n_i$ = number of observations

Putting values in above equation:

$\text{Average molecular weight}=\frac{(\chi_{CH_4}\times M_{CH_4})+(\chi_{C_2H_4}\times M_{C_2H_4})+(\chi_{C_2H_2}\times M_{C_2H_2})+(\chi_{C_2H_2O}\times M_{C_2H_2O})}{4}$

$\text{Average molecular weight of mixture}=\frac{(0.20\times 16)+(0.30\times 28)+(0.35\times 26)+(0.15\times 42)}{4}\\\\\text{Average molecular weight of mixture}=6.75$

Hence, the correct answer is Option d.

3 0

3 years ago

Why do ionic compounds have high melting points?

Vika [28.1K]

These oppositely charged compounds are strongly held by electrostatic forces of attraction as these be together for a long time the rise in temparature occurs so that the the melting points rises in them.

4 0

3 years ago

Which of these is the lowest subgroup? kingdom, order, genus, or species.

olga55 [171]

The correct answer is species

6 0

3 years ago

Read 2 more answers

In your own words what is equilibrium?

fenix001 [56]

Answer:

when the forward and reverse reactions occur at equal rates.

chemical reaction is in equilibrium when the concentrations of reactants and products are constant - their ratio does not vary.

8 0

3 years ago

What is the number of valence electrons in a calcium atom? * 8 2 18 20​

What is the number of valence electrons in a calcium atom? * 8 2 18 20