1. Identify Unknown-1? Sodium Carbonate O Potassium sulfate O Sodium Hydroxide​

The answer should be c.

Nonmetals usually react by gaining electrons

Ans. : frostbite is when exposure to cold temperatures causes freezing to the skin or other tissues. it most commonly affects the hands, feet, and face. the longer areas are exposed to cold, typically the worse the frostbite. the water temperature used for rewarming a frostbitten part should be : (102 -105) f degrees.