When hydrogen gas reacts with oxygen gas, water vapour is formed according to the

Zinc has a specific heat capacity of 0.390 J/goC. What is its molar heat capacity? Enter your answer numerically to three signif

ch4aika [34]

Answer:

The answer to your questions is Cm = 25.5 J/mol°C

Explanation:

Data

Heat capacity = 0.390 J/g°C

Molar heat capacity = ?

Process

1.- Look for the atomic number of Zinc

Z = 65.4 g/mol

2.- Convert heat capacity to molar heat capacity

(0.390 J/g°C)(65.4 g/mol)

- Simplify and result

Cm = 25.5 J/mol°C

3 0

3 years ago

How much heat is needed to boil 45 grams of water at 100°C?

wolverine [178]

Answer:

Depends how much water and the temperature of the water. To heat 1 mL of water by 1 degree C 1 cal of energy (4.184 Joules) is required. Assuming that the water is at 25 degrees C, to boil one litre (liter) of water you would require 75,000 cal or 313.8 kJ.

6 0

3 years ago

Which aqueous solution has the highest boiling point at standard pressure?(1) 1.0 M KC1(aq) (3) 2.0 M KCl(aq)(2) 1.0 M CaC12(aq)

miss Akunina [59]

Answer:

(4) 2.0 M CaCl₂(aq).

Explanation:

Adding solute to water elevates the boiling point.

The elevation in boiling point (ΔTb) can be calculated using the relation:

ΔTb = i.Kb.m,

where, ΔTb is the elevation in boiling point.

i is the van 't Hoff factor.

van 't Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved and the concentration of a substance as calculated from its mass. For most non-electrolytes dissolved in water, the van 't Hoff factor is essentially 1.

Kb is the molal elevation constant of water.

m is the molality of the solution.

(1) 1.0 M KCl(aq):

i for KCl = no. of particles produced when the substance is dissolved/no. of original particle = 2/1 = 2.

suppose molarity = molality, m = 1.0 m,

∴ ΔTb for (1.0 M KCl) = i.Kb.m = (2)(Kb)(1.0 m) = 2(Kb).

(2) 2.0 M KCl(aq):

i for KCl = no. of particles produced when the substance is dissolved/no. of original particle = 2/1 = 2.

suppose molarity = molality, m = 2.0 m,

∴ ΔTb for (1.0 M KCl) = i.Kb.m = (2)(Kb)(2.0 m) = 4(Kb).

(3) 1.0 M CaCl₂(aq):

i for CaCl₂ = no. of particles produced when the substance is dissolved/no. of original particle = 3/1 = 3.