Answer:
Common examples include carbon, sulfur, oxygen, iron, copper, aluminium. Elements are represented by symbols. Compounds are substances made from atoms of different elements joined by chemical bonds. They can only be separated by a chemical reaction.
Explanation:
Substances can be categorised as either elements or compounds. Both of these are made up of atoms, the only difference is an element is made of one type of atom whereas compounds are made of two or more different types of atoms.
Answer:
Water cycle
Explanation:
Water rains from the cloud into the ocean. Then the water gets sucked back up to atmosphere of the clouds
Answer:
Some of the hydrogen bonds with other elements, but most of it remains free hydrogen. Both hydrogen and helium are light elements, so they will tend to evaporate into space over time. ... But the gravity of Earth isn't strong enough, so Earth's early atmosphere of helium and free hydrogen evaporated into space.
Explanation:
The answer is '<span>triploid cell'.
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This occurs when two sperm nuclei reach the interior of a female gametophyte, where one sperm will fertilise the egg cell to form a zygote, whereas the other usually fuses with the binucleate central cell, forming a primary endosperm cell, effectively constituting an organism separate from the growing embryo. Approximately 70% of angiosperm species have polyploid endosperm cells which are typically triploid (containing three sets of chromosomes), but can vary widely from diploid(2n) to 15n.