Answer:
Investigation B, Step 2
Explanation:
The <em>colour change</em> is a good indication of a <em>chemical change</em>. The sugar molecules were most likely changing into something else.
Investigation A, Step 1. <em>Wron</em>g. The dissolving of salt is a <em>physica</em>l process.
Investigation A, Step 2. <em>Wrong</em>. You simply boiled off the water (a <em>physical</em> process) and recovered the salt.
Investigation B, Step 1. <em>Wrong</em>. The dissolving of sugar is a <em>physical</em> process.
<u>Answer:</u> The mole ratio of H : O in ammonium nitrate is 4 : 3.
<u>Explanation:</u>
We are given a compound named ammonium nitrate having formula 
There are 3 elements in this compound which are nitrogen, hydrogen and oxygen.
To calculate the mole ratio, we write the ratio of their subscripts. For this compound, it is:

The mole ratio of H and O for this compound is 4 : 3.
Answer:
water was added to powdered rock
Explanation:
#AB
Electronegativity difference=3.3-2.9=0.4.
- It's a covalent bond.
- Gaseous or solid substance.
#AC
Electronegativity difference=3.3-0.7=2.6
- Its an ionic bond.
- Solid substance.
#BC
Electronegativity difference=2.9-0.7=2.3
- It's an ionic bond
- Solid substance