Hydrogen H weight: 81
Non-metal
Hydrogen is the simplest element; an atom consists of only one proton and one electron. It is also the most plentiful element in the universe. Despite its simplicity and abundance, hydrogen doesn't occur naturally as a gas on the Earth--it is always combined with other elements.
period 1 group 1
Hydrogen is easily the most abundant element in the universe. It is found in the sun and most of the stars, and the planet Jupiter is composed mostly of hydrogen. On Earth, hydrogen is found in the greatest quantities as water.
Answer:
1) Hydrogen
2) Methane
3) Carbon
4) Structural isomer
5) Ethene also known as ethylene
6) Hydrocarbons are widely used as fuel
7) Crude oil
Explanation:
It is an endothermic reaction because the products hAve more heat than the reactions so it was a gain of heat which makes the enthalpy Change positive !
Rechargeable batteries use a reversible reaction medium to convert electrical current to a form of chemical energy which can be stored for future use.
<h3>
What is a rechargeable battery?</h3>
A rechargeable battery is a type of battery that can be charged many times by passing electric current through the cells in a reversible reaction.
<h3>How does recahargeable battery store energy?</h3>
When electrical energy from an outside source is applied to a secondary cell (reachargeable battery), the negative to positive electron flow that occurs during discharge is reversed, and the cell's charge is restored. This process is called reversible reaction.
Thus, rechargeable batteries use a reversible reaction medium to convert electrical current to a form of chemical energy which can be stored for future use.
Learn more about reversible reaction here: brainly.com/question/11412193