If the initial sample is 3.75g what made of the original iridium- 192 remain after 55 days?
Estimate the half-life of the radioisotope.
How many days would it take for two-thirds is the sample to decay?

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

How many moles of bromine are needed to produce 3.23 moles of potassium bromide

What information does a complete ionic equation give that the balanced equation doesn’t show?