I’m the lightest element and float in balloons. What element am I?

I help your blood carry oxygen. What element am I?

I’m liquid at room temperature and toxic. Used in thermometers once. What element am I?

I keep your bones strong and I’m found in dairy. What element am I?

I glow in the dark and was once used in watch dials. What element am I?

I’m essential for life, make up water, and fuel the Sun. What element am I?

I’m used in light bulbs and don’t react easily. What element am I?

I’m used in batteries and can be explosive. What element am I?

I’m a yellow, smelly element often linked with volcanoes. What element am I?

I make up most of the air you breathe. What element am I?