Answer:
elements
Matter that has only one kind of atom is called an element. Gold, copper, oxygen, and mercury are examples of elements. Most matter is made up of two or more different kinds of atoms that are chemically combined. This kind of matter is called a compound.
Explanation:
Acid base reactions also known as neutralization reactions are reactions that occur between acids and bases thus the name. Anytime this happens the product will niether an acid or base it will be neutralized to a neutral pH as in that of pure water pH 7.
Precipitation reactions occur when cations and anions in aqueous solution combine to form an insoluble ionic solid called a precipitate. Whether or not such a reaction occurs can be determined by using the solubility rules for common ionic solids.
The given question is incomplete. The complete question is:
A brick has a mass of 4.0 kg and the earth has a mass of
Use this information to answer the questions below. Be sure your answers have the correct number of significant digits. What is the mass of 1 mole of bricks? Round your answer to 2 significant digits. How many moles of bricks have a mass equal to the mass of the Earth? Round your answer to 2 significant digits.
Answer: The mass of 1 mole of bricks is 
2.5 moles of bricks have a mass equal to the mass of the Earth
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to its molecular mass and contains avogadro's number
of particles.
Mass of 1 brick = 4.0 kg = 4000 g (1kg=1000g)
Thus mass of 1 mole of brick or
bricks will be = 
The mass of 1 mole of bricks is 
Now
will correspond to = 1 mole of bricks
will correspond to =
2.5 moles of bricks have a mass equal to the mass of the Earth