Answer:
2 atoms
Explanation:
1 sodium atom + 1 chlorine atom = 2 atoms
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:
8.13x10^22 molecules
Explanation:
We can use the Avogadro's number(6.022 x 10^23 units / mole)
2.30 g NH3 (1 mol / 17.03 g ) (6.022 x 10^23 molecules / 1 mol ) = 8.13x10^22 molecules
Hope this helps! Feel free to ask any questions!
Answer:
Mg(OH)2 + 2HCI ⇒ MgCI2 + 2H2O
Explanation:
In order to balance a chemical equation you need to make sure both sides of the equations are equal.
Mg(OH)2 + 2HCI = MgCI2 + H2O
Mg = 1
Oh = 2
HCI = 2
Products:
Mg = 1
CI = 2
H = 2
O = 1
2H20 = 1 × 2 = 2
2 × 2 = 4
2HCI
1 × 2 = 2
Mg(OH)2 + 2HCI ⇒ MgCI2 + 2H2O
Hope this helps.
