The answer is heat.
To use a glue gun, it has to use heat to heat up so that it can melt the glue.
Answer:
Explanation: A yellow precipitate o lead iodide is formed. see equation of reaction below:
→ 
Th PbI2 is the insoluble yellow precipitate
Answer: 17) d. 
18. c. The empirical formula of a compound can be twice the molecular formula.
Explanation:
Molecular formula is the chemical formula which depicts the actual number of atoms of each element present in the compound.
Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.
To calculate the molecular formula, we need to find the valency which is multiplied by each element to get the molecular formula.
The equation used to calculate the valency is:

The empirical mass can be calculated from empirical formula and molar mass must be known.
17. Thus the empirical formula of
should be 
18. The molecular formula will either be same as empirical formula or is a whole number multiple of empirical formula. Thus the empirical formula of a compound can never be twice the molecular formula.
Answer:
It is because water is liquid and it can be weathered easily. While weathering by solid is a bit dangerous because of its hardness.
Explanation:
I put the answer <em>C: Keq will increase</em>, on PLATO. Hope this works for you!