Particles are smaller, a reactant would be exposed to more cobalt atoms. Causing the reaction to happen quicker than with larger particles.
Answer:
The empirical formula is ZnO2
Explanation:
What is the empirical formula for a compound which contains 67.1% zinc and the rest is oxygen?
Step 1: Data given
Suppose the compound has a mass of 100.0 grams
A compound contains:
67.1 % Zinc = 67.1 grams
100 - 67.1 = 32.9 % oxygen = 32.9 grams
Molar mass of Zinc = 65.38 g/mol
Molar mass of O = 16 g/mol
Step 2: Calculate moles of Zinc
Suppose the compound is 100 grams
Moles Zn = 67. 10 grams / 65.38 g/mol
Moles Zn = 1.026 moles
Step 3: Calculate moles of O
Moles O = 32.90 grams / 16.00 g/mol
Moles O = 2.056 moles
Step 4: Calculate mol ratio
We divide by the smallest amount of moles
Zn: 1.026/1.026 = 1
O: 2.056/1.026 = 2
The empirical formula is ZnO2
To control this we can calculate the % Zinc for 1 mol
65.38 / (65.38+2*16) = 0.67.1 = 67.2 %
Answer:
THE LENGTH OF THE AIR COLUMN IS 9.5 CM
Explanation:
Taking the atmospheric pressure to be 760 mmHg;
When the capillary tube is held horizontally, the pressure of the tube is 760 mmHg
when the capillary tube is held vertically, the pressure increases by 4 cm = 40 mm
The new pressure of the tube is hence, 760 + 40 mmHg = 800 mmHg
Using the pressure forlmula;
P1 V1 = P2 V2
P1 A1 L1 = P2 A2 L2
where A1 and A2 is the area of the capillary tube and it is equal, it cancels out.
P1 l1 = P2 l2
l2 = P1 l1 / P2
l2 = 760 * 10 / 800
l2 = 9.5 cm
The length of the air in the tube is 9.5 cm.
pH solution = 8.89
<h3>Further explanation</h3>
Given
The concentration of HBr solution = 1.3 x 10⁻⁹ M
Required
the pH
Solution
HBr = strong acid
General formula for strong acid :
[H⁺]= a . M
a = amount of H⁺
M = molarity of solution
HBr⇒H⁺ + Br⁻⇒ amount of H⁺ = 1 so a=1
Input the value :
[H⁺] = 1 x 1.3 x 10⁻⁹
[H⁺] = 1.3 x 10⁻⁹
pH = - log [H⁺]
pH = 9 - log 1.3
pH = 8.89