Which of the following metals is not found in the free state?

Due to low ionization energy,alkali metals are...

Which of the following metals releases hydrogen gas upon reaction with cold and dilute $HNO_3$?

The correct statement$(s)$ among $I$ to $III$ with respect to potassium ions that are abundant within the cell fluids is/are :
$I.$ They activate many enzymes
$II.$ They participate in the oxidation of glucose to produce $ATP$
$III.$ Along with sodium ions,they are responsible for the transmission of nerve signals

What are the metal ions present in carnallite?

What is Soda ash?