30ml of a 2.50 M hydrochloric acid solution is required to make 100.0 mL of a 0.750 M solution.
<h3>What is HCl?</h3>
HCl is an acid which is made up of hydrogen and chlorine gas.
By the formula of dilution
M1V1 = M2V2
where V1 = 2.50 m
M2 = 100.0
V2 = 0.750 m
M1 × 2.50 m = 100.0 × 0.750 m
M1 = 30 ml
Thus, the M1 is 30 ml option a is correct.
Learn more about HCl
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Answer:
Molar mass→ 0.930 g / 6.45×10⁻³ mol = 144.15 g/mol
Explanation:
Let's apply the formula for freezing point depression:
ΔT = Kf . m
ΔT = 74.2°C - 73.4°C → 0.8°C
Difference between the freezing T° of pure solvent and freezing T° of solution
Kf = Cryoscopic constant → 5.5°C/m
So, if we replace in the formula
ΔT = Kf . m → ΔT / Kf = m
0.8°C / 5.5 m/°C = m → 0.0516 mol/kg
These are the moles in 1 kg of solvent so let's find out the moles in our mass of solvent which is 0.125 kg
0.0516 mol/kg . 0.125 kg = 6.45×10⁻³ moles. Now we can determine the molar mass:
Molar mass (mol/kg) → 0.930 g / 6.45×10⁻³ mol = 144.15 g/mol
Answer:
Carbon Dioxide fire extinguishers extinguish fire by taking away the oxygen element of the fire triangle and also be removing the heat with a very cold discharge. Carbon dioxide can be used on Class B & C fires. They are usually ineffective on Class A fires
