consider the following chemical compounds: MnO2,NaHCO3,Na2CO3 NH4CL and Pb ( NO3)2. Which of them has black color, is a basic oxide, sublime on heating, dissolves in water to give a solution of pH less than 7.

The answer is d.potassium

C) the increase in atmospheric pressure pushes the walls of the balloon outward thus making it  is the answer.hope i you.

The answer to the question: choose the correct statement.  a) when ethane reacts with fluorine gas the product is less stable.b) addition reactions of unsaturated hydrocarbons and halogens requires a high activation energy.  c)the double covalent bond within unsaturated hydrocarbons requires a lot of energy to break.  d)the double covalent bond within unsaturated hydrocarbons can be broken easily.is: a) when ethane reacts with fluorine gas the product is less stable.

The answer is  d.  hydrogen