Answer:
0.43×10²³ atoms
Explanation:
Given data:
Mass of LiBrO₂ = 4.28 g
Number of atoms of oxygen = ?
Solution:
Number of moles = mass/molar mass
Number of moles = 4.28 g/ 118.84 g/mol
Number of moles = 0.036 mol
We can see 1 mole of LiBrO₂ contain 2 mole of oxygen atm.
0.036 mol × 2 = 0.072 mol
1 mole contain 6.022×10²³ atoms
0.072 mol × 6.022×10²³ atoms / 1mol
0.43×10²³ atoms
Grease and non-polar too, so the <span>tetrachloroethylene would be a solvent.</span>
<h3>1. <u>Answer</u>;</h3>
= 5.4×10-6 g AgBr
<h3><u>Explanation</u>;</h3>
AgBr(s) → Ag+(aq) + Br-(aq) Ksp = 3.3×10^-13
[Ag+][Br-] = Ksp = 3.3×10^-13 = X²
X = 5.7×10^-7 M = [Ag+] = mol/L AgBr that dissolve
1 mole of AgBr = 187.8 g
Therefore;
= 0.05 L × (5.7 × 10^-7 mol/L) × (187.8 g /mol)
= 5.4×10-6 g AgBr
<h3>2. <u>Answer and explanation;</u></h3>
The two factors that accounts for increased rate of chemical reaction when temperature is increased are:
- <u>Energy factor</u>; enough energy in the collision for the formation of an activated complex, where bonds are breaking and new ones forming. When temperature is increased, a greater number of molecular collisions possess enough energy to activate the reaction.
- <u>Frequency of collisions increases;</u> an increase in temperature makes particles move faster and collide more frequently, increasing the possibility of a reaction be-tween them.
More important factor; Energy factor is more important.
The <span>statement about ice melting that is true is that the </span><span>temperature of the ice increases as it melts. The answer is letter D. The rest of the choices do not answer the question above.</span>