Cesium-137 has a half-life of 30 years. You find a sample with 3 g of cesium-137. How much cesium-137 existed in the sample 90 years ago?

The digestive system is a group of organs working together to convert food into energy and basic nutrients that are transported throughout the body.

Simple machines make work easier. Most simple machines reduce the amount of effort force needed to move an object. This cart has a set of wheels. The wheels are actually simple machines: the wheel and axle.

What happens to the concentration of a solution when you add solute?

Physics vs organic chemistry which is harder

Hans buys a bag of fertilizer at the store. It reads 30-15-10. How much nitrogen is in the fertilizer?

An animal that backs on a warm rock during the morning hours but retreats to the shade of the rocks during the middle of the day is mostly likely a (n) A. ectotherm B. endotherm C. vertebrate D. chordate

How much water vapor can a cubic meter of air hold at 25 degrees celcius

When 0.50 L of a 12 M solution is diluted to 1.0 L, what is the resulting molarity?

A 52.9g sample of brass, which has a specific heat capacity of 0.375·J·g-1°C-1, is put into a calorimeter (see sketch at right) that contains 100.0g of water. The temperature of the water starts off at 15.0°C.

What is the concentration of 10.00 mL of HBr if it takes 16.73 mL of a 0.253 M LiOH solution to neutralize it?