Answer:
1. Mass of potassium (K) = 203.32 g
2. Number of mole of As = 7.53 moles
Explanation:
1. Determination of the mass of potassium (K)
Molar mass of K = 39.1 g/mol
Number of mole of K = 5.2 moles
Mass of K =.?
Mole = mass / Molar mass
5.2 = mass of K / 39.1
Cross multiply
Mass of K = 5.2 × 39.1
Mass of potassium (K) = 203.32 g
2. Determination of the number of mole of Arsenic (As)
Molar mass of As = 74.92 g/mol
Mass of As = 563.9 g
Number of mole of As =.?
Mole = mass /Molar mass
Number of mole of As = 563.9 / 74.92
Number of mole of As = 7.53 moles
Answer:
The new volume if the balloon is cooled at constant pressure is 3.98 L
Explanation:
The new volume is calculated using the Charles law formula
that is V1/ T1 = V2/T2 where,
V1 = 4.24 l
T1= 23c into kelvin = 23 +273 =296 K
T2 = 5.00 c into kelvin = 5.00 + 273 = 278 K
V2 = ?
by making V2 subject the subject of the formula by multiplying both side by T2
V2 = V1 xT2/ T1
V2 = (4.24 L x 278 K) / 296 k = 3.98 L
(2) gains 12 moles of electrons, easy, because it must retain the same mass in a balanced equation, so if there is no exterior mention of any electrons, such as the notation +12e-, than we must assume that the Oxygen took it at any rate.
The balanced chemical reaction is written as:
2H2+O2 = 2H2O
We are given the amount of H2 gas to be used in the reaction. This will be used as the starting point for the calculations. We calculate as follows:
.050 L H2 ( 1 mol H2 / 22.4 L H2 ) ( 1 mol O2 / 2 mol H2 ) ( 22.4 L / 1 mol ) = 0.025 L O2 or 25 mL O2
Answer:
A. Any substance with a pH above 7.
Explanation:
On the pH scale substances whose value is greater than 7 and less than 14 are termed alkali.
Acids have a pH of less than 7 whereas neutral compounds such as water has pH of 7.
- An alkali is any substance that produces excess hydroxyl ion in solutions.
- Water soluble bases are known as alkali.
- They are usually certain metallic oxides, metallic hydroxides and aqueous ammonia.
