Answer:
ρ = 1.08 g/cm³
Explanation:
Step 1: Given data
Mass of the substance (m): 21.112 g
Volume of the substance (V): 19.5 cm³
Step 2: Calculate the density of the substance
The density (ρ) of a substance is equal to its mass divided by its volume.
ρ = m / V
ρ = 21.112 g / 19.5 cm³
ρ = 1.08 g/cm³
The density of the substance is 1.08 g/cm³.
Answer:
Q = 1360.248 j
Explanation:
Given data:
Mass of brass = 298.3 g
Initial temperature = 30.0°C
Final temperature = 150°C
Specific heat capacity of brass = 0.038 J/g.°C
Heat absorbed = ?
SOLUTION:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 150°C - 30.0°C
ΔT = 120°C
Q = 298.3 g × 0.038 J/g.°C × 120°C
Q = 1360.248 j
Answer:
Approximately .
Explanation:
Balanced equation for this reaction:
.
Look up the relative atomic mass of elements in the limiting reactant, , as well as those in the product of interest, :
Calculate the formula mass for both the limiting reactant and the product of interest:
.
.
Calculate the quantity of the limiting reactant () available to this reaction:
.
Refer to the balanced equation for this reaction. The coefficients of the limiting reactant () and the product () are both . Thus:
.
In other words, for every of formula units that are consumed, of formula units would (in theory) be produced. Thus, calculate the theoretical yield of in this experiment:
.
Calculate the theoretical yield of this experiment in terms of the mass of expected to be produced:
.
Given that the actual yield in this question (in terms of the mass of ) is , calculate the percentage yield of this experiment:
.
We will get the molality from this formula:
Molality = no.of moles of solute / Kg of solvent
So first we need the no.of moles of KNO3 = the mass of KNO3 / molar mass of KNO3
no.of moles of KNO3 = 175 / 101.01 = 1.73 mol
By substitution in the molality formula:
∴ molality = 1.73 / (750/1000) = 2.3 Molal