Answer:
13.75
Explanation:
gets halved every 8 days so halved twice
Answer:
b. 3.66x10²³ atoms of chromium.
Explanation:
First we calculate how many moles are there in 31 grams of chromium, using its molar mass:
- Molar Mass of Chromium = 51 g/mol (This can be found on any periodic table)
- 31 g ÷ 51 g/mol = 0.608 mol
Then we <u>calculate how many atoms are there in 0.608 moles</u>, using <em>Avogadro's number</em>:
- 0.608 mol * 6.023x10²³ atoms/mol = 3.66x10²³ atoms
The correct answer is thus option b. 3.66x10²³ atoms of chromium.
Answer:
A combination reaction
Explanation:
The chemical reaction between ammonia and hydrochloric acid as shown below:
NH₃ + HCl → NH₄Cl
is a combination reaction.
In a combination reaction, two compounds combines together to give one compound.
A combination reaction is also known as a synthesis reaction.
A single product forms from tow or more reactants.
The driving force for such reaction is the large and negative heat of formation of the product.
D.) a transformation of light energy into chemical energy
<h3><u>Answer</u>;</h3>
= 226 Liters of oxygen
<h3><u>Explanation</u>;</h3>
We use the equation;
LiClO4 (s) → 2O2 (g) + LiCl, to get the moles of oxygen;
Moles of LiClO4;
(500 g LiClO4) / (106.3916 g LiClO4/mol)
= 4.6996 moles
Moles of oxygen;
But, for every 1 mol LiClO4, two moles of O2 are produced;
= 9.3992 moles of Oxygen
V = nRT / P
= (9.3992 mol) x (8.3144621 L kPa/K mol) x (21 + 273) K / (101.5 kPa)
= 226 L of oxygen
