Answer: The first step is testing their theory!
Explanation: Scientists will have to set up an experiment to scientifically prove their statement/hypothesis:)
Answer:

Explanation:
Range = Highest value - Lowest value
A 'soft solder' melts between 183 °C and 212 °C.
Melting range of a 'soft solder' = 
A 'hard solder' melts between 620 °C and 680 °C.
Melting range of a 'hard solder' = 
So,
Difference in melting ranges = Melting range of a 'hard solder' - Melting range of a 'soft solder' = 
Answer:
the answer is B =the weighted average of the masses of the isotopes of the element
Answer:
Relative molecular of the compound or infomation like vapour density, volume occupied by a known mass of its vapour at stp, etc
Explanation:
The molecular mass of a compound is twice its vapour density. We can find the molecular formula using the relationship below:
- Empirical formula is the simplest formula of a compound. It repeats itself "n" times to become a molecular formula i.e (EF)ₙ = MF...... n is the number of times the empirical formula presents in a mole of the compound.
- Most times, n is a whole number like 1,2,3,.....