Answer:Four types of vaccines are currently available: Live virus vaccines use the weakened (attenuated) form of the virus. The measles, mumps, and rubella (MMR) vaccine and the varicella (chickenpox) vaccine are examples
Answer:
I think it should be Hafnium which is Hf.
<h2>D.
They contain the same number of elements.</h2>
Explanation:
The formula (Ba(NO3)2) contains 9 atoms.
1 Barium atom (Ba)
Contains 2 NO3 groups -
2 Nitrogen atoms (N) x 2
6 Oxygen atoms (O3) x 2
3 Elements in total
The formula (Sc(NO3)3) contains 13 atoms.
1 Scandium atom (Sc)
Contains 3 NO3 groups -
3 Nitrogen atoms (N) x 3
9 Oxygen atoms (O3) x 3
3 Elements in total
They do not have the same number of atoms.
They do not have the same number of oxygen atoms.
They do not contain the same number of NO3 groups.
They do have the same number of elements.
