What is a substance that cannot be broken down further by chemical means

The environment needs to what for natural selection to occur

Mg (OH) 2 + HCl - - > MgCl2 + H2O

A 10.0 g ice cube is placed into 250 g of water with an initial temperature of 20.0 C. If the water drops to a temperature of 16.8 C, has a specific heat of 4.18 J/g*K, what is the enthalpy of fusion of the ice.

Describe and explain all the possible energy transformations that occur with a dishwasher that uses electrical energy

What determines the mass number of an element? the number of protons minus the number of electrons the number of protons the total number of protons, electrons, and neutrons the total number of neutrons and protons

The envelope of air that surrounds the earth is called

What is the chemical formula for potassium permanganate?

Is it always possible to identify something as an element compound pure substance or mixture

Why would someone weigh less on Pluto?

HNO3 + H2O > H3O (aq) + NO3 - (aq)