Answer:
A. The actual number of atoms in a molecule
Explanation:
Molecular formula is simply defined as a type of chemical formula that describes the type and number of atoms present in a single molecule of a compound.
Looking at the options, the correct answer is option A.
This<span> will require'' </span>266.9kJ''<span> of heat energy
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To calculate the energy required to raise the temperature of any given substance, here's what you require:
The mass of the material, <span>m</span>
The answer would be 200000 J. the equation for kinetic energy is 1/2 mass times velocity squared. 1/2 of 1,000 is 500. and 20*20 is 400. So, multiply 400 by 500, and that gives you your answer,
Li2S + 2 HNO3 --> 2 LiNO3 + H2S
Li2 S + H2 N2 O2 --> Li2 N2 O5 + H2 S
Li S + H2 N2 O5 -> Li N2 O5 + H2 S
Li2 S2 + H4 N4 O10 --> Li2 N4 O10 + H4 S2
Li^2 S^2 + H^4 N^4 O^10 --> Li^2 N^4 O^10 + H^4 S^2
As with the properties of a substance, the changes that substances undergo can be classified as either physical or chemical. During physical changes a substance changes its physical appearance, but not its composition. The evaporation of water is a physical change.
(I searched that up but here’s an explanation with my own words that you can use):
Change in matter can be classified as a physical change as well as a chemical change due to the properties of substance. A physical change changes substance within its appearance but not its composition. For an example: The evaporation of water is a physical change.
There you go hopefully that helped