Answer:
The answer is A. Polar covalent; negatively
Explanation:
Hydrogen bonds form between molecules containing polar covalent bond the hydrogen bond is been a hydrogen atom of one molecule and a partially negative charged atom of another.
Example 
(water):- It contain a slight positive charge on one side and a slight negative charge on the other.
Answer: Fireworks exploding is a chemical change.
Explanation: Lighting gunpowder, and making the explosion is a chemical change.
Answer:Reaccionan 54gr de Nitrato de plata al 39 % de pureza, con 72gr de ácido clorhídrico al 83% de pureza, en un proceso donde se obtienen 93 gr de cloruro de - 154… ... 93 gr de cloruro de plata. El otro producto es el ácido nítrico: Calcular el porcentaje de rendimiento de la reacción y balancearlo.
