B
A qualitative observation describes the characteristics of a substance without quantifying them.
Answer:
D, Li2S
Explanation:
This is because Lithium, which is in group IA of the periodic table, has a charge of +1. Sulfur will have a charge of -2 because it is in group 6A in the periodic table, which means to balance these out, there needs to be 2 lithium ions which would result in a charge of +2. With Lithium now having a charge of +2 due to having two atoms in the compound, and sulfur already having a charge of -2 as one atom, these two cancel out meaning the compound is neutral.
Reactants are the substance that undergo a change in a chemical reaction while products are what is produced after a reaction. don't have time to write a reaction.
A- Change the phase of the matter
Answer:
Explanation:
A measurement is the action of measuring something, or some amount of stuff. So it is important to measure certain things right, distance, time, and accuracy are all great things to measure. By measuring these things or in other words, by taking these measurements we can better understand the world around us.