Answer is: molality od sodium chloride is 2,55 mol/kg.
V(solution) = 100 ml.
m(solution) = d(solution) · V(solution).
m(solution) = 1,10 g/ml · 100 ml.
m(solution) = 110 g.
ω(NaCl) = 13,0% = 0,13.
m(NaCl) = ω(NaCl) · m(solution).
m(NaCl) = 0,13 · 110 g.
m(NaCl) = 14,3 g.
n(NaCl) = m(NaCl) ÷ M(NaCl).
n(NaCl) = 14,3 g ÷ 58,5 g/mol.
n(NaCl) = 0,244 mol.
m(H₂O) = 110 g - 14,3 g.
m(H₂O) = 95,7 g = 0,0957 kg.
b(NaCl) = n(NaCl) ÷ m(H₂O).
b(NaCl) = 0,244 mol ÷ 0,0957 kg.
b(NaCl) = 2,55 mol/kg.
The arrangement of atoms in a mineral can change its physical and chemical properties.
Diamonds and coal are both made of carbon, however, their chemical and physical properties are very different.
Answer:
The specific heat for the titanium metal is 0.524 J/g°C.
Explanation:
Given,
Q = 1.68 kJ = 1680 Joules
mass = 126 grams
T₁ = 20°C
T₂ = 45.4°C
The specific heat for the metal can be calculated by using the formula
Q = (mass) (ΔT) (Cp)
Here, ΔT = T₂ - T₁ = 45.4 - 20 = 25.4°C.
Substituting values,
1680 = (126)(25.4)(Cp)
By solving,
Cp = 0.524 J/g°C.
The specific heat for the titanium metal is 0.524 J/g°C.
Liquid + Solid = 8.89 mL
V ( Solid ) = 8.89 mL - 6.26 mL = 2.63 mL
The density of the solid = m / V = 10.283 g / 2.63 mL =
= 3.9 g/mL = 3.9 g / cm³
If he was 30.8% too low, it means that he was at 69.2% of the boiling point needed. So 50o C is 69.2% of total.
In order to know what 100% is, you can divide the number by it's percentage and then multiply it by a hundred.
So: 50/30.8=1.623
1.623*100=162.3
So the correct boiling point of the liquid he was working with in the lab is 162.3 oC
