36inches in the air first bounce second bounce 15
Answer:

Explanation:
When water changes from ice (solid) to water (liquid), it is melting or fusion. Therefore, we can use the following formula to find energy:

where <em>q</em> is the energy, <em>m </em>is the mass, and <em>Hf</em> is the heat of fusion.
1. Define Values
The mass is 150 grams. The heat of fusion for water is 334 Joules per gram.

2. Calculate Energy
Substitute the values into the formula.

Multiply. Note that the grams (g) will cancel each other out and leave Joules as our units.


3. Convert Units
We found the answer in joules, but the question asks for kilojoules, so we must convert.
There are 1000 Joules in 1 kilojoule. Therefore, we can divide the joules calculated by 1000.



<u>50.1 kilojoules </u>are needed to change 150 grams of ice to water.
Answer:
THE MOLARITY IS 2.22 MOL/DM3
Explanation:
The solution formed was as a result of dissolving 37.5 g of Na2S in 217 g of water
Relative molecular mass of Na2S = ( 23* 2 + 32) = 78 g/mol
Molarity in g/dm3 is the amount of the substance dissolved in 1000 g or 1 L of the solvent. So we have;
37.5 g of Na2S = 217 g of water
( 37.5 * 1000 / 217 ) g = 1000 g of water
So, 172.81 g/dm3 of the solution
So therefore, molarity in mol/dm3 = mol in g/dm3 / molar mass
Molarity = 172.81 g/dm3 / 78 g/mol
Molarity = 2.22 mol/dm3
The molarity of the solution is 2.22 mol/dm3