Density= mass/volume
= 100/25
density = 4g/ml
So, you need to have same ammount of atoms on the left and on the right side of the equation. You need to count the ammount of attoms of every substance on the left, and make sure that on the right side the ammount is same. For example in the 1st one it’s 6Sn+2P4=2Sn3P4, so that you have 6atoms of Sn on the left and 6 atoms of Sn on the right, same with the P
The alveoli are surrounded<span> by tiny blood vessels, called capillaries. The </span>alveoli<span> and capillaries both have very thin walls, which allow the oxygen to pass from the </span>alveoli<span>to the blood. The capillaries then connect to larger blood vessels, called veins, which bring the oxygenated blood from the lungs to the heart.</span>
Ionic compounds form when metals transfer valence electrons to nonmetals. Ionic compounds exist as crystals rather than molecules.