Answer:
It is important to separate mixture into pure or relatively pure substances when performing a chemical analysis SO AS TO KNOW THE PROPERTIES COMING FROM EACH PART MIXTURE WHICH MAY INTERFERE WITH THE SEPARATION.
Explanation:
In chemistry, Mixture is the combination of two or more substances which are not combine chemically.
Mixture contain different substances with different physical and chemical properties.
It is important to purify the substances in a mixture so as to identify what properties are coming from each mixture and also some part of the mixture can interfere with the properties of other mixture present for skewing analysis.
Answer:
Ordinary table salt is called sodium chloride. It is considered a substance because it has a uniform and definite composition. All samples of sodium chloride are chemically identical. Water is also a pure substance. Salt easily dissolves in water, but salt water cannot be classified as a substance because its composition can vary. You may dissolve a small amount of salt or a large amount into a given amount of water. A mixture is a physical blend of two or more components, each of which retains its own identity and properties in the mixture . Only the form of the salt is changed when it is dissolved into water. It retains its composition and properties.
Homogeneous Mixtures
A homogeneous mixture is a mixture in which the composition is uniform throughout the mixture. The salt water described above is homogeneous because the dissolved salt is evenly distributed throughout the entire salt water sample. Often it is easy to confuse a homogeneous mixture with a pure substance because they are both uniform. The difference is that the composition of the substance is always the same. The amount of salt in the salt water can vary from one sample to another. All solutions would be considered homogeneous because the dissolved material is present in the same amount throughout the solution.
One characteristic of mixtures is that they can be separated into their components. Since each part of the mixture has not reacted with another part of the mixture, the identities of the different materials is unchanged.
Answer : There are 7.0 moles of oxygen in the formula.
Explanation :
The chemical formula of nickel tetracarbonyl is Ni(CO)₄.
We can see that there are 4 carbon atoms and 4 oxygen atoms which together form 4 carbonyl (CO) groups.
Therefore the mole ratio of C to O is 1 : 1.
Let us use this as a conversion factor to find moles of oxygen.
We have 7.0 moles of carbon in the formula.
The moles of O can be calculated as,

There are 7.0 moles of oxygen in the formula.