. Look at the periodic table, how much does one mole of a Hydrogen atom weigh? Why is the molar mass of hydrogen (H2) 2.02 g/mol in the example 1 above?

Agroup of students is studying convection current. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other is in an area with warm air. after 10 minutes, the balloon are released from a height of 1 meter. which of the following to the students most likely observe? a) the warm balloon expands and rises. the cold balloon shrinks and sinks b) the balloon both rise. the cold balloon is larger than the warm balloon c) the cold balloon expands and rises. the warm balloon shrinks and sinks d) the balloon rise at the same rate. both balloons are the same size

Apiece of metal with a length of 1.42 cm was measured using four different instruments. which of the following measurements is the most accurate?

What is the chemical formula for the compound formed between sodium and flour one