The first question's answer is
Among the choices given, the correct answer is the first option. Substance X most likely is a crystal, and substance Y most likely is a liquid. Substance X having a fixed volume describes a crystal because crystals occupy a certain volume. Substance Y is a liquid because liquids can still be compressed further in order to attain a more packed <span>structure.</span>
Answer:
Endothermic
Explanation:
Storing sugar for later use is an example of an endothermic reaction because that energy is being absorbed.
Answer:
A
Explanation:
To label an element correctly using a combination of the symbol, mass number and atomic number furnishes some important information about the element.
We can obtain these information from the element provided that correct labeling of the element is presented. Firstly, after writing the symbol of the element, the atomic number is placed as a subscript on the left while the mass number of the atomic mass is placed as a superscript on the same left.
Looking at the question asked, we have the element symbol in the correct position as Ca, with 42 also in the correct position which is the mass number. The third number which is 20 is thus the atomic number of the element.
