12.3 moles of sodium is what mass of Na?

A substance is analyzed and found to contain 85.7% carbon and 14.3% hydrogen by weight. A gaseous sample of the substance is fou

atroni [7]

Answer:

The empirical formula of the compound is CH2

Explanation:

Step 1: Data given

A substance contains 85.7 % carbon and 14.3 % hydrogen.

The substance has a density of 1.87 g/L

1 mol occupies 22.4 L

Molar mass of carbon = 12 g/mol

Molar mass of hydrogen = 1.01 g/mol

Step 2: Calculate molar mass of the substance

Since 1 mol occupies 22.4 L;

1 mol of this substance = 1.87g/L *22.4 = 41.888 grams

This means the molar mass of the substance is 41.888 g/mol

Step 3: Calculate mass of carbon:

85.8 % is carbon

this means 41.888 * 0.858 = 35.94 grams

Step 4: Calculate moles of carbon

moles C = mass C/ Molar mass C

Moles C = 35.94 grams / 12 g/mol

Moles C = 2.995 moles

Step 5: Calculate mass of hydrogen:

14.3 % is hydrogen

this means 41.888 * 0.143 = 5.99 grams

Step 6 :Calculate moles of hydrogen

Moles H = 5.99 grams / 1.01 g/mol

Moles H = 5.93 moles

Step 7: Calculate mol ratio

Ratio C:H = 1:2

The empirical formule = CH2

Step 8: calculate molar formule

Molar mass of empirical formule = 14.02 g/mol

n = Molar mass of substance / molar mass of empirical formule

n = 41.888 / 14.02 = 3

This means we have to multiply the empirical formula by 3

3*(CH2) = C3H6

C3H6 can be propene or cyclopropane

5 0

2 years ago

HELP NOW Do Now 3.5 Purple

Serga [27]

Answer:

The smell of a chocolate is from the presence of volatile compounds present in the chocolate bar which at room temperature readily changes phase from solid to liquid to vapor or gas

Explanation:

There are nearly 600 identified compounds present in a chocolate bar and out of these, there are volatile components which gives the chocolate bar its distinctive aroma.

These volatile chocolate contents readily change phase from solid to vapor, with very short duration liquid phase.

For example, 3 methylbutanal, vanillin, and several organic compounds which are known to be readily volatile.

4 0

2 years ago

What is the concentration of an naoh solution that requires 15.0 ml of a 0.750 m h2so4 solution to neutralize 17.5 ml of naoh?

e-lub [12.9K]

So the first thing we must do is write a balanced equation for the reaction and we know the equation is balnced when all the species on the RHS is equal to the species on the LHS
2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O

So now it's time to identify what reactant you know the most for from the question (volume & conc. of H₂SO₄) and use that info to find the unknown (conc. of NaOH)

If 1000 ml of H₂SO₄ contain 0.750 mol [0.750 M is the amount of moles in
1 L (1000 ml)]
then let 15 ml of H₂SO₄ contain x mol [15 ml is the amount of the acid that took part in the reaction]

⇒ x = $\frac{15ml * 0.750 mol}{1000 ml}$

= 0.01125 mol

Mole ratio of NaOH to H₂SO₄ can be obtained from the balanced equation
0 2NaOH + 1H₂SO₄ → Na₂SO₄ + 2H₂O

mole ratio of NaOH to H₂SO₄ is 2 : 1

∴ if mole of of H₂SO₄ = 0.01125 mol
 then moles of NaOH = (0.01125 mol) × 2
= 0.0225 mol

If 17.5 ml of NaOH contain 0.0225 mol [this was given in the question]
then let 1000 ml of NaOH contain x

⇒ x = $\frac{1000ml * 0.0225 mol}{17.5 ml}$

= 1.286 mol

∴ concentration of NaOH is 1.286 mol/L

8 0

3 years ago

What are two reasons that ICl has a low melting point?

vovangra [49]

Answer:

1. It is a covalent bond and all covalent bonds have low melting points

Explanation:

3 0

2 years ago

When HCl(g) reacts with NH3(g) to form NH4Cl(s), 42.1 kcal of energy are evolved for each mole of HCl(g) that reacts. Write a ba

stich3 [128]

Answer: The chemical equation is $HCl(g)+NH_3(g)\rightarrow NH_4Cl(s)+42.1kCal$

Explanation:

There are 2 types of reactions that are classified based on enthalpy change:

Endothermic reaction
Exothermic reaction

Endothermic reactions: They are defined as the reactions where heat is absorbed by the reaction. The change in enthalpy of the reaction is always positive.

Exothermic reactions: They are defined as the reactions where heat is released by the reaction. The change in enthalpy of the reaction is always negative.

Given values:

Energy released for 1 mole of HCl reacted = -42.1 kCal

The chemical equation for the formation of ammonium chloride follows:

$HCl(g)+NH_3(g)\rightarrow NH_4Cl(s)+42.1kCal$

8 0

2 years ago

12.3 moles of sodium is what mass of Na?​

12.3 moles of sodium is what mass of Na?