Matter can be broken down into two categories: pure substances and mixtures. Pure substances are further broken down into elements and compounds. Mixtures are physically combined structures that can be separated into their original components. A chemical substance is composed of one type of atom or molecule
2NH₂ + O₂ → N₂ + 2H₂O
<u>Explanation:</u>
Balancing the equation means, the number of atoms on both sides of the equation must be the same.
In the case of the given equation, we have to find out whether it is balanced or not.
2NH₂ + O₂ → N₂ + 2H₂O
Atoms Number of atoms before balancing after balancing
LHS RHS LHS RHS
N 1 2 2 2
H 2 2 4 4
O 2 1 2 2
To balance the N atoms, we have to put 2 in front of NH₂, and then to balance the H, O atoms, we have to put 2 in front of H₂O, so that each atom in left hand as well as right hand side of the equation was balanced.
Answer:
A gas is evolved
The ingredients can not be recovered
Explanation:
A chemical change is one in which a new substance is formed and it is not easily reversible.
One major ingredient used in cake baking is the baking powder or baking soda.
Baking a cake can be viewed as a chemical change. This is because, when the baking powder or soda is added in the presence of yeast, carbon dioxide gas is evolved as tiny bubbles of gas which makes the cake light and fluffy. Heat is equally given off in the process. The baking powder and other cake ingredients can not be recovered, hence, we can conclusively assert that a chemical change has taken place.
