Unit' is the word used to describe how something is measured. When researching a question in science, we collect data, interpret it, and share the results with other scientists. A common measurement system allows us to make direct comparisons instead of having to know things like how much a certain animal weighs.
Answer:
Molar mass of MgCO3 = 84.3 g/mol
Explanation:
What is the molar mass of magnesium carbonate.
Molar mass of a substance is defined as the mass of one mole of the substance expressed in grams hence its unit is gram per mole (g/mol)
MgCO3 is a compound and it's molar mass would be the sum of the molar masses of the elements that make up the compound. MgCO3 contains 1 atom of magnesium, one atom of carbon and 3 atoms of oxygen
Molar mass of Magnesium = 24.3g
Molar mass of Carbon =12g
Molar mass of Oxygen = 16g
Molar mass of MgCO3 will be
24.3 + 12 + 16×3
= 24.3 + 12 +48 = 84.3 g/mol
Molar mass of MgCO3 = 84.3 g/mol
<span><span>Number of Protons-19 </span><span>Number of Neutrons-20 </span><span>Number of Electrons-<span>19</span></span></span>
The balanced reaction is given as:
<span>2Ca(s)+O2(g)→2CaO(s)
</span>
We are given the amount of oxygen gas to be used for the reaction. This will be the starting point of our calculations.
0.016 mol O2 ( 2 mol CaO / 1 mol O2 ) = 0.032 mol CaO
<span>Therefore, for the reaction, the amount of calcium oxide produced is 0.032 moles.</span>
<u>Answer:</u> In heterogeneous mixture, the composition remains variable throughout.
<u>Explanation:</u>
For the given options:
Homogeneous mixtures are defined as the mixtures that appears uniformly throughout the solution and the particle size or shapes are not different. The composition remains constant throughout.
A solution is defined as the solution in which the components gets completely dissolved in it. Particles are evenly spread in these solutions. These solution does not scatter light falling on it. The composition remains constant throughout.
An amorphous solid is defined as the solid in which the constituent particles of the matter are arranged in the random manner. The composition remains constant throughout.
A heterogeneous mixture is defined as the mixture in which component are unevenly spread throughout the solution. The size and shape of the particles differ in these mixtures. These mixture scatter the light falling on it. The composition do not remains constant throughout.
Compound is defined as the chemical specie which is formed by the combination of two or more different type of atoms. <u>For Example:</u> 
etc...The composition remains constant throughout.
Hence, in heterogeneous mixture, the composition remains variable throughout.
