SCIENCE
CHEMISTRY
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Pure Substance
|
|
|
Mixture
|
|
|
Either A or B
|
|
|
None of the above
|
Detailed explanation-1: -A sample of helium is composed of only helium atoms. Hence it is classified as a pure substance.
Detailed explanation-2: -Helium gas is a PURE SUBSTANCE because is only contains a single element in its composition.
Detailed explanation-3: -He is a pure substance. There is only one type of particle. As such, we classify He as a pure substance and not a mixture. Mixtures contain two or more elements.
Detailed explanation-4: -Helium is an example of a pure substance because it is a collection of helium atoms in the gas state.
Detailed explanation-5: -All elements are mostly pure substances. A few of them include gold, copper, oxygen, chlorine, diamond, etc. Compounds such as water, salt or crystals, baking soda amongst others are also grouped as pure substances.