Answer:
1.35 × 10⁴ kg/m³ at 22 °C; 1.34 × 10⁴ kg/m³ at 100 °C
Explanation:
The cubic expansivity (γ) of a liquid is the fractional change in volume per unit change in temperature.
Multiply by V₀ΔT and transpose
ΔV = γV₀ΔT
and
V = V₀ + ΔV
===============
<em>At 0 °C
</em>
Assume you have 1 m³ of Hg
ρ = m/V Multiply by V and transpose
m = ρV
ρ = 1.36 × 10⁴ kg/m³
m = 1.36 × 10⁴ × 1 = 1.36 × 10⁴ kg
===============
<em>At 22 °C
</em>
Assume that you have 1 m³ of Hg
γ = 180 × 10⁻⁶ K⁻¹
ΔT = 22 °C – 0 °C = 22 °C
ΔV = 180 × 10⁻⁶ × 22
ΔV = 3.96 × 10⁻³ m³ Calculate volume
V = 1 + 0.00396
V = 1.00396 m³ Calculate density
ρ = 1.36 × 10⁴/1.00396
ρ = 1.35 × 10⁴ kg/m³
===============
<em>At 100 °C
</em>
ΔT = 100 °C – 0 °C = 100 °C
ΔV = 180 × 10⁻⁶ × 100
ΔV = 0.0180 m³ Calculate volume
V = 1 + 0.0180
V = 1.0180 m³ Calculate density
ρ = 1.36 × 10⁴/1.0180
ρ = 1.34 × 10⁴ kg/m³
Infrared waves, micro waves, radio waves because they are weaker.
Answer:
80mg
Explanation:
Given parameters:
Density of Platinum metal = 21.4g/mL
Dimension of the metal = 3cm by 0.03m by 40mm
Unknown:
Weight of the metal in milligrams?
Solution:
Density is the mass per unit volume of a substance.
Mathematically;
Density = 
Volume of the platinum metal = l x w x h
Let us convert the dimension of the metal to the same unit;
3cm x 0.03m x 40mm
convert to cm;
100m = 1cm
0.03m = 
= 0.0003cm
-- 40mm;
1mm = 0.1cm
40mm = 40 x 0.1 = 4cm
Volume of the metal = 3 x 0.0003 x 4 = 0.0036cm³
1mL = 1cm³; so volume = 0.0036mL
Mass of the metal = 21.4 x 0.0036 = 0.08g
1g = 1000mg
0.08g = 0.08 x 1000 = 80mg
V(C₄H₆O₃) = 5.00 mL.
d(C₄H₆O₃) = 1.08 g/mL.
m(C₄H₆O₃) = V(C₄H₆O₃) · d(C₄H₆O₃).
m(C₄H₆O₃) = 5.00 mL · 1.08 g/mL.
m(C₄H₆O₃) = 5.4 g.
n(C₄H₆O₃) = m(C₄H₆O₃) ÷ M(C₄H₆O₃).
n(C₄H₆O₃) = 5.4 g ÷ 102 g/mol.
n(C₄H₆O₃) = 0.0529 mol.
n(C₇H₆O₃) = 2.08 g ÷ 138.1 g/mol.
n(C₇H₆O₃) = 0.015 mol; limiting reactant.
From chemical reaction: n(C₄H₆O₃) : n(C₉H₈O₄) = 1 : 1.
n(C₉H₈O₄) = 0.015 mol.
m(C₉H₈O₄) = 0.015 mol · 180.16 g/mol.
m(C₉H₈O₄) = 2.71 g; theoretical yield.
percent yield od aspirine = 2.57 g ÷ 2.71 g · 100% = 94.83%.
