Question

is the number of stomata in the leaves of all plants? explain

Answer 1

I can't tell because No, even single leaf of a plant doesn't have same no.of stomata throughout it's life. Thenumber of stomata on leaf surfaces varies widely among different species of plants. 

Answer 2

No, even single leaf of a plant doesn't have same no.of stomata throughout it's life. The number of stomata on leaf surfaces varies widely among different species of plants. The lower epidermis of the leaf tends to have a higher total than the upper surface. The average number of stomata is about 300 per square mm of leaf surface. The smallest number is found on Tradescantia (spiderwort) leaves which have 14 per square mm. The highest number of stomata is 1200 per square mm on leaves of the Spanish oak tree. Stomata are found on conifer needles as well as on the broad leaves of angiosperms.
Stomata found on the bottom surface of a pine leaf. There are several environmental factors that affect the number of stomata on a leaf. Researchers have evidence which indicates that stomata densities change in response to changing atmospheric levels of carbon dioxide. This suggests that as global warming progresses (due to rising levels of atmospheric carbon dioxide) the number of stomata per leaf may increase, allowing the plant to absorb more carbon dioxide. Other factors that can increase stoma density are an increase in light or amount of rainfall.