An unknown compound contains only C , H , and O . Combustion of 8.90 g of this compound produced 20.2 g CO2 and 8.28 g H2O . What is the empirical formula of the unknown compound

For ai it's atomic number is 13 and it's mass number is 27 how many neutrons does it have

Select each correct answer. more than one answer may be correct. which of the following is a characteristic of unicellular organisms? they can possess tissues and organs. all of their functions are performed by a single cell. they are usually microscopic. each of their cells is specialized to perform a specific function.

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