Please can anyone check if the paragraph about gaseous exchange correct?

Air containing oxygen is inhaled and taken into the alveoli of the lungs. The oxygen diffuses into the blood capillaries and it is taken to the heart. In the cells, oxygen is used for rexpiratory by mitochondria to release energy into the blood and reaches the alveoli in the lungs. Carbon dioxide and water diffuses into lungs and finally passed out through the mouth or nose.