Number of moles :
n = mass solute / molar mass
n = 20 / 18
n = 1.111 moles
Therefore:
Molarity = moles solute / volume
Molarity = 1.111 / 30 => 0.37 M
Answer:
0.500 mol/dm³
Explanation:
Using the formula below;
CaVa = CbVb
Where;
Ca = concentration of acid (mol/dm³)
Cb = concentration of base (mol/dm³)
Va = volume of acid (cm³)
Vb = volume of base (cm³)
In accordance to the information provided in this question is;
Va = 5cm³
Vb = 250 cm³
Ca = 12 mol/dm³
Cb = ?
Using CaVa = CbVb
12 × 5 = Cb × 250
60 = 120Cb
Cb = 60/120
Cb = 0.500 mol/dm³
The reaction is:
Cl2 + 2 KBr --> 2 KCl + Br2
Moles of KCl is
n = m /M = 12 /74 = 0.16 mol
As, twice the moles of KCl is producing from 1 mol of chlorine
mole of Cl2 = 0.16 /2 = 0.08 mol
Mass of Cl2
m /70 = 0.08 = 5.6 g
Hence, 5.6 g mol Cl2 consumed to produce KCl
To solve this we assume that the hydrogen gas is an
ideal gas. Then, we can use the ideal gas equation which is expressed as PV =
nRT. At a constant pressure and number of moles of the gas the ratio T/V is
equal to some constant. At another set of condition of temperature, the
constant is still the same. Calculations are as follows:
T1 / V1 = T2 / V2
V2 = T2 x V1 / T1
V2 = (100 + 273.15) K x 2.50 L / (-196 + 273.15) K
<span>V2 = 12.09 L</span>
Therefore, the volume would increase to 12.09 L as the temperature is increased to 100 degrees Celsius.
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Answer:
0.13 g
Explanation:
mass of aluminum required = ( Dislocation length) / ( Dislocation density) × (density of metal)
3000 miles to cm ( 1 mile = 160934 cm) = 3000 miles × 160934 cm / 1 mile = 482802000 cm
density of Aluminium = 2.7 g /cm³
dislocation density of aluminum = 10¹⁰ cm³
mass of aluminum required = (482802000 cm × 2.7 g/cm³) / 10¹⁰ cm³ = 0.13 g
