Answer:
A coffee cup calorimeter is great for measuring heat flow in a solution, but it can't be used for reactions that involve gases since they would escape from the cup. The coffee cup calorimeter can't be used for high-temperature reactions, either, because they would melt the cup.
It is an element. Aluminun foil is aluminum prepared in thin leaves.
Answer:
31.9 °C
Explanation:
The formula for the heat q absorbed by an object is
q = mCΔT where ΔT = (T₂ - T₁)
Data:
q = 12.35 cal
m = 19.75 g
C = 0.125 cal°C⁻¹g⁻¹
T₂ = 37.0 °C
Calculations
(a) Calculate ΔT
q = mCΔT
12.35 cal = 19.25 g × 0.125 cal°C⁻¹g⁻¹ × ΔT
12.35 = 2.406ΔT °C⁻¹
ΔT = 12.35/(2.406 °C⁻¹) = 5.13 °C
(b) Calculate T₂
ΔT = T₂ - T₁
T₁ = T₂ - ΔT = 37.0 °C - 5.13 °C = 31.9 °C
The original temperature was 31.9 °C.
Answer:
4.05 × 10²² atoms
Explanation:
Step 1: Given data
Mass of nickel: 3.95 g
Step 2: Calculate the moles corresponding to 3.95 g of nickel
The molar mass of nickel is 58.69 g/mol.
3.95 g × (1 mol/58.69 g) = 0.0673 mol
Step 3: Calculate the atoms in 0.0673 moles of nickel
We will use Avogadro's number: there are 6.02 × 10²³ atoms of nickel in 1 mole of atoms of nickel.
0.0673 mol × (6.02 × 10²³ atoms/1 mol) = 4.05 × 10²² atoms
