E is related to a period of elements by generally decreasing from right to left. The correct answer is 2.
Answer:
Explanation:
BrO3- (aq) + Sb^3+ (aq) --------> Br^3- (aq) + Sb^5+ (aq) is an unbalanced equation and needs to be balanced
BrO3- (aq) → Br^3- (aq
to balance it water must be added to the right side and H⁺ be added to the left side
BrO₃⁻ + 6 H⁺ + 8e⁻ → Br³⁻ + 3 H₂ O
Sb³⁺ (aq) → Sb⁵⁺ + 2e⁻
multiply the second equation by 4
BrO₃⁻ + 6 H⁺ + 8e⁻ → Br³⁻ + 3 H₂ O
4Sb³⁺ → 4Sb⁵⁺ + 8 e⁻
add the two equation together and cancel the 8 e electrons on both side
BrO₃⁻ + 4Sb³⁺ + 6 H⁺ → Br³⁻ + 4Sb⁵⁺ + 3 H₂ O
number of mole of BrO₃⁻ = volume in liters × molarity = (29.9 / 1000) L × 0.120 M = 0.003588 moles
from the balanced equation of reaction;
one mole of BrO₃⁻ requires 4 moles of Sb³⁺
0.003588 moles of BrO₃⁻ will require = 0.003588 × 4 = 0.0144 moles of Sb³⁺
a) amount of antimony in grams in the sample = 0.0144 moles × 121.8 g ( molar mass of antimony) = 1.748 g
b ) percentage of antimony in the ore = 1.748 g / 6.33 g = 27.62 %
Answer:
S + 4 Cl2
Explanation:
Sulphur - S
1 mol of Sulphur = S
Chlorine = Cl2
4 moles of Chlorine = 4Cl2
4S + 2Cl2
Incorrect option
S + 4 Cl2
Correct option
S + 2Cl2
Incorrect option
S + Cl2
Incorrect option
This one was too easy it's CCl4
We can use the ideal gas law equation to find the volume occupied by the gas
PV = nRT
where
P - pressure - 1.33 atm x 101 325 Pa/atm = 134 762 Pa
V - volume
n - number of moles - 18.0 g / 4 g/mol = 4.5 mol
R - universal gas constant - 8.314 Jmol⁻¹K⁻¹
T - temperature in Kelvin - 29 °C + 273 = 302 K
substituting these values in the equation
134 762 Pa x V = 4.5 mol x 8.314 Jmol⁻¹K⁻¹ x 302 K
V = 83.8 L
volume occupied by He is 83.8 L