Answer:
The molarity (M) of the following solutions are :
A. M = 0.88 M
B. M = 0.76 M
Explanation:
A. Molarity (M) of 19.2 g of Al(OH)3 dissolved in water to make 280 mL of solution.
Molar mass of Al(OH)3 = Mass of Al + 3(mass of O + mass of H)
= 27 + 3(16 + 1)
= 27 + 3(17) = 27 + 51
= 78 g/mole
= 78 g/mole
Given mass= 19.2 g/mole
Moles = 0.246
Volume = 280 mL = 0.280 L
Molarity = 0.879 M
Molarity = 0.88 M
B .The molarity (M) of a 2.6 L solution made with 235.9 g of KBr
Molar mass of KBr = 119 g/mole
Given mass = 235.9 g
Moles = 1.98
Volume = 2.6 L
Molarity = 0.762 M
Molarity = 0.76 M
Answer:
It's coefficient to the front of each element that requires it.
Explanation:
It is coefficient to the front of each element or compound that requires it. Essentially you are multiplying the amount of atoms or compounds on one side to match the amount on the other side.
Combustible: Charcoal, straw, cardboard, paper, candle, wood.
Non-combustible: Chalk, stone, iron rod, copper coin, glass.
Answer:
Compound
Explanation:
We want to know if it's a compound or a mixture.
An example of a mixture is salt water: you can heat it hot enough to boil off the water, leaving only the salt. This is a physical change, which is how you know it's a mixture.
Something like gold is a compound: if you heat it, or hit it, you'll still only have gold. You can only break it down by chemical means, which is how you know it's a compound.
6 inches of snowfall would be equivalent to 6/11 inches of water or 6/132 feet. So the volume of the equivalent amount of water on the roof is 150 ft. x 45 ft. x 6/132ft. = 306.8 cubic feet.
Since there are 907185 grams in a ton and 28316.8 mL in a cubic foot, 1.00 g/mL is equivalent to 0.0312 tons/cubic foot
Multiplying the two results gives 9.58 tons of snow.
