Select which of the following statements are true about ions: A positively charged particle and a negatively charged particle attract each other Two negatively charged particles attract each other
A positively charged particle and a negatively charged particle repel each other
Two positively charged particles attract each other

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

Which of the following electromagnetic waves can create ions?

Find the number of grams of hcl needed to react completely with .50 moles of magnesium.