Dalton model :) Hope this helped.
Answer: The student’s values are accurate as well as precise.
Explanation:
Precision refers to the closeness of two or more measurements to each other.
For Example: If you weigh a given substance three times and you get same value each time. Then the measurement is very precise.
Accuracy refers to the closeness of a measured value to a standard or known value.
For Example: If the mass of a substance is 50 kg and one person weighed 49 kg and another person weighed 48 kg. Then, the weight measured by first person is more accurate.
Given: Mass = 5.000 g
Mass weighed by A has values 4.891 g , 4.901 g and 4.890. Thus the average value is 
Thus as the measured value is close to the true value, the student’s values are accurate and as the values are close to each other, the measurement is precise.
It's called "Ionic compound"
-
Menirals have definite chemical composition
- Minerals have crystalline structure
<u>Explanation:</u>
Minerals should be found in nature. Elements made laboratories are not actual minerals like masquerading as rubies or sapphires. All naturally available crystals are not minerals like opal and amber.
Minerals are not under any class of organic compounds. Almost all known minerals come from inorganic processes. Some minerals originate from organic processes like pearls.
Minerals exist only as solids. Solids have a defined volume and shape, and they cannot be compressed any further. Minerals are rigid.
- Definite chemical composition
Each mineral has a unique combination of atoms that cannot be found in other minerals. The strength of mineral can be defined by the type of bond a mineral has. Some minerals, like gold and diamond, have only one element in it.
Minerals form crystals that have repeated arrangements of ions. Minerals have different shapes depending on the size of the ion. Crystals usually take six types of shapes.
