A rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition and the way in which it is formed
Answer:
The correct answer is option A, that is, one valence electron in its third energy shell and option C, that is, 11 electrons and 11 protons.
Explanation:
The outermost electrons and the ones that take part in the process of bonding are termed as valence electrons. The atomic number of sodium is 11, thus, it possesses 11 protons and the atoms are neutral so it suggests that sodium has 11 electrons. By electronic configuration, it can be seen that in sodium, two electrons are present in the first shell, 8 in the second, and only one electron in the third shell, that is, 2.8.1. The electron present in the third shell is the valence electron.
Answer:
Fill in the blanks with the correct term.
a. a liquid that dissolves another substance.
b. a chemical that is dissolved.
c. a value used to describe the amount of one substance dissolved in another.
d. a liquid consisting of one substance dissolved in another.
Explanation:
a. A liquid that dissolves another substance is called the solvent.
b. A chemical that is dissolved solute.
c. A value used to describe the amount of one substance dissolved in another is called concentration.
d. A liquid consisting of one substance dissolved in another is called a solution.
Answer:
Absorbed, endothermic
Explanation:
Based on the heat of reaction, chemical reactions may be classified as endothermic or exothermic.
In an endothermic reaction, heat is absorbed from the surrounding. As heat is absorbed from the surrounding, the reaction vessel feels cool when touched.
On the other hand, in an exothermic reaction, heat is given out by the system to the surrounding and the reaction vessel feels hot when touched.
Hence the reaction is endothermic and energy is absorbed during the reaction.
