Guys what is valency in chemistry please I need help I will give brainlest pleas help

Why did southern business leaders want to increase the number of slaves

Why is the melting of ice a physical change ?

Which of the following is a conclusion that resulted from ernest rutherford’s scattering experiment? (will mark brainliest) a. the nucleus is negatively charged b. the atom is a dense solid and is indivisible c. the mass is conserved when atoms react chemically d. the nucleus is very small and the atom is mostly empty space