<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
Explanation:
As the given data is as follows.
Height, H = 150 feet
Heat gain = 30,000 BTU/hr, and Heat loss = 25000 BTU/hr
m = mass of water heated = 700 gallons = 5810 lbs
is the heat capacity of water = 1 BTU/lb 
(given)
= temperature difference = 
Heat energy required to heat 700 gal can be calculated as follows:
Heat Required = 
Thus, water rises till 
.
Answer:
Explanation:
I think none of the above, because when caused by a UV light it damages the cells. And if enough builds up overtime it causes uncontrollable growth and leads to skin cancer.
Hope that helped? It might be another answer honestly.
10 is mixture of elements and compounds
11 is compound
12-15 are mixture of compounds
