How much of a 24-gram sample of Radium-226 will remain unchanged at the end of three half-life periods?

At element makes up all organic compounds?

40dm3 of gas at 760 torr are heated from 5°c to 50°c what is the new volume

In science class richard learns that a substance has a boiling point of 230 fahrenheit his teacher ask him to convert this temperature to degrees celsius what is the boiling point of his substance in degrees celsius