<span>Ag2S
Ag(silver) has a charge of 1+
S2-(Sufide has a charge 2-
you need balance
charge have to equal to zero so you need 2 silvers and one sulfide
to have equilibrium</span>
Answer:
2.7 °C.kg/mol
Explanation:
Step 1: Calculate the freezing point depression (ΔT)
The normal freezing point of a certain liquid X is-7.30°C and the solution freezes at -9.9°C instead. The freezing point depression is:
ΔT = -7.30 °C - (-9.9 °C) = 2.6 °C
Step 2: Calculate the molality of the solution (b)
We will use the following expression.
b = mass of solute / molar mass of solute × kilograms of solvent
b = 102. g / (162.2 g/mol) × 0.650 kg = 0.967 mol/kg
Step 3: Calculate the molal freezing point depression constant Kf of X
Freezing point depression is a colligative property. It can be calculated using the following expression.
ΔT = Kf × b
Kf = ΔT / b
Kf = 2.6 °C / (0.967 mol/kg) = 2.7 °C.kg/mol
Answer:
The answer is "10.84 g".
Explanation:
The formula for calculating the number for moles:

In the given acid nitric:
Owing to the nitric acid mass = 
Nitric acid molar weight
If they put values above the formula, they receive:


In the given chemical equation:

In this reaction, 2 mols of nitric acid are produced by 1 mole of water.
So, 1.204 moles of nitric acid will be produced:

We are now using Equation 1 in determining the quantity of water:
Water moles 
Water weight molar 


Answer:
Helium nuclei is emitted during alpha decay.
Explanation:
Alpha radiations are emitted as a result of radioactive decay. The atom emit the alpha particles consist of two proton and two neutrons. Which is also called helium nuclei. When atom undergoes the alpha emission the original atom convert into the atom having mass number 4 less than and atomic number 2 less than the starting atom.
Properties of alpha radiation:
Alpha radiations can travel in a short distance.
These radiations can not penetrate into the skin or clothes.
These radiations can be harmful for the human if these are inhaled.
These radiations can be stopped by a piece of paper.
Example:
₉₂U²³⁸ → ₉₀Th²³⁴ + ₂He⁴ + energy