<h3>
Answer:</h3>
2.125 g
<h3>
Explanation:</h3>
We have;
- Mass of NaBr sample is 11.97 g
- % composition by mass of Na in the sample is 22.34%
We are required to determine the mass of 9.51 g of a NaBr sample.
- Based on the law of of constant composition, a given sample of a compound will always contain the sample percentage composition of a given element.
In this case,
- A sample of 11.97 g of NaBr contains 22.34% of Na by mass
A sample of 9.51 g of NaBr will also contain 22.345 of Na by mass
% composition of an element by mass = (Mass of element ÷ mass of the compound) × 100
Mass of the element = (% composition of an element × mass of the compound) ÷ 100
Therefore;
Mass of sodium = (22.34% × 9.51 g) ÷ 100
= 2.125 g
Thus, the mass of sodium in 9.51 g of NaBr is 2.125 g
Kr look on periodic table it's krypton elements
Answer:
slippery, often used as cleaning products, have a high pH, things like bleach and laundry detergent
Explanation:
Answer:
19.91 J/K
Explanation:
The entropy is a measure of the randomness of the system, and it intends to increase in nature, thus for a spontaneous reaction ΔS > 0.
The entropy variation can be found by:
ΔS = ∑n*S° products - ∑n*S° reactants
Where n is the coefficient of the substance. The value of S° (standard molar entropy) can be found at a thermodynamic table.
S°, Cl(g) = 165.20 J/mol.K
S°, O3(g) = 238.93 J/mol.K
S°, O2(g) = 205.138 J/mol.K
So:
ΔS = (1*205.138 + 1*218.9) - (1*165.20 + 1*238.93)
ΔS = 19.91 J/K