C. Frequency is a measure of how many waves pass by in one second.
The question is incomplete, the complete question is;
Eli states that sodium phosphate is a mixture because it is composed of both sodium ions and phosphate ions. Which is the best analysis of Eli’s statement? It is correct because each ion is a pure substance, so sodium phosphate is made up of two pure substances. It is correct because the composition of sodium phosphate changes depending on the sample. It is incorrect because sodium phosphate is a compound that has a single composition. It is incorrect because the two types of ions in sodium phosphate cannot be seen.
Answer:
It is incorrect because sodium phosphate is a compound that has a single composition
Explanation:
A compound is a neutral substance made up of two or more atoms which are chemically combined together.
Ionic substances are made up of ions. These ions are not separate entities, they are part of the compound.
Hence, Eli's statement is incorrect because sodium phosphate is a compound that has a single composition.
Answer: C. Some of uranium's mass is converted into energy, so the smaller atoms have less mass.
Explanation:
From Einstein's mass-energy relation:
E = mc²
Mass and energy are equivalent. Mass can be converted into energy and energy into mass.
When Uranium atoms under go nuclear fission, smaller atoms are formed and huge amount of energy is released. This energy comes from the mass difference of the uranium nuclei and new nuclei formed. This mass converted into energy according to Einstein's equation.
Answer: Planting a tree belt.
Explanation:
The most effective method by which the desertification of the soil can be controlled is by planting more and more trees.
The process of desertification occurs when there is a loss of vegetation, water bodies and animals from a particular area. Loss of trees makes the area look like desert.
So, planting trees along with some irrigation will help to cope with problem.
