2. F is non-metal, because it has seven electrons (more that 3)
3.It <span>fills its shell by gaining one electron, because it is easier to gain 1 e⁻ than to loose 7 e⁻.
4. It </span><span>becomes a negatively charged ion, because atom of F is neutral, it has "0" charge, and it takes one negatively charged electron(-1). (0 +(-1)= -1)</span>
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: B
Explanation: molarity = concentration c= n/V = 0.5 mol/ 0.05 l = 10 mol/l
The best substance to heat up the fastest would be blue fire