15 questions
What is the total number of atoms present in 5Na3PO4? (remember, a coefficient is a multiplier and Elements without a number is 1)
5
55
40
8
What is the right part of a chemical equation called?
2H2 + O2 ---> 2H2O
Reactants
Yields
Products
Chemical Equation
What is the little number after an element in a chemical equation called?
Example: H2
Coefficient
Atom
Subscript
Equation
What is the number before a chemical formula called?
Example: 2H2 + O2 ---> 2H2O
Coefficient
Atom
Subscript
Equation
In the equation, 2Mg + O2 ---> 2MgO, which are the reactants?
Mg and O
Mg and MgO
MgO
O and MgO
Balance this equation:
H2 + Cl2 ---> HCl
It is balanced.
H2 + Cl2 ---> 2HCl
3H2 + Cl2 ---> 6HCl
H2 + 3Cl2 ---> 6HCl
Balance this equation:
HgO ---> 2Hg + O2
It is balanced.
2HgO ---> 2Hg + O2
2HgO ---> Hg + O2
HgO ---> Hg + 2O2
The compound ammonia is composed of nitrogen and hydrogen atoms. If two atoms of nitrogen completely react with six atoms of hydrogen to form two molecules of ammonia, which best describes the number of hydrogen atoms present in the two molecules of ammonia?
2
4
6
A chemistry teacher combines 20 grams of lemon juice with 25 grams of baking soda in a flask covered with a balloon. The flask and balloon have a combined mass of 105 grams. What is the mass of the entire setup after a reaction has occurred?
45 g
150 g
605 g
What coefficients are needed to balance the following chemical equation?
__Zn + __HCl → __ZnCl2 + __H2
1,1,1,1
1,2,1,1
2,1,2,2
2,1,2,1