Iron rusts when exposed to air → chemical property
Answer:
C
Explanation:
A negative deltaH means that the reaction has to give up heat in order to happen. You have to treat deltaH as a reactant. So the question is do you need to add heat to the reactants to make the products. If you do, deltaH is plus.
Heat is required to make a solid go to a gas. deltaH is plus. A is not the answer.
A lot of heat is required for B (something like 400 Kj / mole. Like A, deltaH is plus and B is not the answer.
C: The liquid has to give up heat in order for the this reaction to take place. C is the answer.
D requires heat. It is not the answer.
Answer:
Substitution mutation
Explanation:
A substitution mutation is a type of mutation in which one or more nucleotide base is replaced by another in a sequence. This will result in the replacement of one or more amino acid in the amino acid sequence.
This is the case in this question where the original amino acid sequence was given as: Leucine – Alanine – Glycine – Leucine. After mutation, the following mutated sequence was produced: Leucine – Alanine – Valine – Leucine.
As illustrated above, one would notice that there is replacement of GLYCINE amino acid by VALINE in the mutated sequence, hence, it is an example of SUBSTITUTION MUTATION.
Answer: Option (d) is the correct answer.
Explanation:
In solids, molecules are held together by strong intermolecular forces of attraction. As a result, they are unable to move from their initial position and can only vibrate at their mean position.
Hence, a solid has definite shape and volume. Solids cannot be compressed.
Whereas in plasma, molecules are hot ionized which include positively charged ions and negatively charged electrons. They collide much more rapidly with each other and are widely spreaded out.
Therefore, they occupy the volume of container in which they are placed. Plasma can be compressed.
Thus, we can conclude that substance X is a solid and substance Y is a plasma.
