Wube

Suppose vectors a&b if a x b=c. Show that c is perpendicular to a&b. Please help me.

Hydrogen atoms are excited to the stationary state designated by the principal quantum number, n= 4. What will be the number of lines(frequencies) emitted by the hydrogen atoms?

What are the possible values of the azimutal quantum number for an electron in the 4f subshell?

When the equation for the following reaction in basic solution is balance, what is the sum of the coefficients? MnO2 + HO2^1-.....>MnO4^1- A=11 B=31 C=14 D=9

Thank u so much for your help!