Answer:
8.55 × 10²⁴ Ions
Explanation:
Ammonium Chloride is an ionic compound which contains a monatomic anion (Cl⁻ ; Chloride) and a polyatomic cation (NH₄⁺ ; Ammonium).
Hence, when added in water Ammonium Chloride ionizes as;
NH₄Cl → NH₄⁺ + Cl⁻
Hence, we can say that it produces two ions when dissolved in water.
Also,
We know that 1 mole of any substance contains exactly 6.022 × 10²³ particles which is also called as Avogadro's Number. So in order to calculate the number of ions contained by 7.1 moles of NH₄Cl, we will use following relation to first calculate the number of molecules as;
Moles = Number of Molecules ÷ 6.022 × 10²³ Molecules.mol⁻¹
Solving for Number of Molecules,
Number of Molecules = Moles × 6.022 × 10²³ Molecules.mol⁻¹
Putting values,
Number of Molecules = 7.1 mol × 6.022 × 10²³
Number of Molecules = 4.27 × 10²⁴ Molecules
So,
As,
1 Molecule of NH₄Cl contained = 2 Ions
So,
4.27 × 10²⁴ Molecules of NH₄Cl will contain = X ions
Solving for X,
X = 2 Ions × 4.27 × 10²⁴ Molecules / 1 Molecule
X = 8.55 × 10²⁴ Ions
Answer:
The heat needed to warm 25.3 g of copper from 22°C to 39°C is 165.59 Joules.
Explanation:

Where:
Q = heat absorbed or heat lost
c = specific heat of substance
m = Mass of the substance
ΔT = change in temperature of the substance
We have mass of copper = m = 25.3 g
Specific heat of copper = c = 0.385 J/g°C
ΔT = 39°C - 22°C = 17°C
Heat absorbed by the copper :

The heat needed to warm 25.3 g of copper from 22°C to 39°C is 165.59 Joules.
Answer:
Explanation:
exothermic reactions involve release of heat whereas endothermic reaction involve absorption of heat.
True
The main chemicals in air pollution that create acid rain are sulfur dioxide (SO2) and nitrogen (NOx).