Aliquid used to dissolve a solid is referred to as: a catalyst a solvent an inhibitor an indicator

Different isotopes indicate that an element will have different numbers of

2. you__turn left on a red light if you are in the left-most lane of a one-way street, you're turning into the left-most lane of a one-way street, and no nearby sign prohibits the turn.

Explain which group an element with the electron configuration 1s2 2s2 2p6 3s2 3p6 3d1 4s2 belongs to.