Answer:
We are heating the sample repeatedly to become a pure compound of only MgSO4 (withot H2O) and a constant mass.
Explanation:
Step 1: Data given
Mass of MgSO4·7H2O = 5.06 grams
The remaining MgSO4 had a constant mass of 2.47 grams.
Step 2: Explain why the sample in the crucible was heated repeatedly until the sample had a constant mass.
Before heating the compound has magnesium sulfate and water.
The total mass of this compound is 5.06 grams
By heating we try to eliminate the water.
After heating there remain mgSO4 with a mass of 2.47 grams
This means 5.06 - 2.47 = 2.59 grams is water. All of this is eliminated.
The heating process happens repeatedly to make sure the final compound is pure. So the 2.47 grams os only MgSO4. If the mass would not be constant. It means the compound is not pure, the not all the water is eliminated yet.
So we are heating the sample repeatedly to become a pure compound of only MgSO4 (withot H2O) and a constant mass.
3 Mg + 1 Fe2O3 →2 Fe + 3MgO
Type of Reaction: Single displacement.
Answer: The theoretical yield is 6 rings.
Explanation:
Theoretical yield is predicted or estimated value.
Jeweler used 2 sapphires for 1 ring
Then for each sapphire there will be = 
rings are used
For 12 sapphire = 
will be used
Out of 10 rings 6 rings with 2 sapphires will be made.
The theoretical yield is 6 rings.
The isotopes are the elements with same atomic number but different atomic mass or mass number
The mass number is denoted by Z
The mass number is denoted by A
The number of neutrons = N
We know that for an element
A = Z + N
As given the element is indium , its atomic number = Z = 49
Z = 49, A = 113 N = 64, This could be an isotope of indium
Z = 49 N = 61, A = 113 , this could also be an isotope of indium
A = 110, N = 49 it means Z = Z - N = 110-49 = 61 So this is not isotope of indium
