Answer:
63.05% of MgCO3.3H2O by mass
Explanation:
<em>of MgCO3.3H2O in the mixture?</em>
The difference in masses after heating the mixture = Mass of water. With the mass of water we can find its moles and the moles and mass of MgCO3.3H2O to find the mass percent as follows:
<em>Mass water:</em>
3.883g - 2.927g = 0.956g water
<em>Moles water -18.01g/mol-</em>
0.956g water * (1mol/18.01g) = 0.05308 moles H2O.
<em>Moles MgCO3.3H2O:</em>
0.05308 moles H2O * (1mol MgCO3.3H2O / 3mol H2O) =
0.01769 moles MgCO3.3H2O
<em>Mass MgCO3.3H2O -Molar mass: 138.3597g/mol-</em>
0.01769 moles MgCO3.3H2O * (138.3597g/mol) = 2.448g MgCO3.3H2O
<em>Mass percent:</em>
2.448g MgCO3.3H2O / 3.883g Mixture * 100 =
<h3>63.05% of MgCO3.3H2O by mass</h3>
Explanation:
A.
In a diprotic acid, 2 moles of H+ ions is released. Therefore, number of moles of H+ in a diprotic acid = 2 × number of moles of H+ of monoprotic acid.
B.
Equation of the reaction
2NaOH + H2SO4 --> Na2SO4 + 2H2O
Number of moles of H2SO4 = molar concentration × volume
= 0.75 × 0.0105
= 0.007875 moles.
By stoichiometry, since 1 mole of H2SO4 reacts with 2 moles of NaOH. Therefore, number of moles of NaOH = 2 × 0.007875
= 0.01575 moles.
Molar concentration of NaOH = number of moles ÷ volume
= 0.01575 ÷ 0.0175
= 0.9 M of NaOH.
Food molecules contain biochemical energy which is made available by a process called respiration.
Respiration is the process within cells by which living things break down food chemicals in their bodies and use them as a source of energy.
The proteins, lipids and polysaccharides that make up most of the food we eat must be broken down into smaller molecules before our cells can use them either as a source of energy or as building blocks for other molecules. This process is named catabolism and occurs in 3 stages.
Stage 1 is the enzymatic breakdown of food molecules in the digestion process into their monomer subunits- amino acids, glucose and glycerol.
Stage 2 is the process of glycolysis where each molecule of glucose is converted to pyruvate.
Stage 3 is production of ATP, the form of energy needed by the body to function. This stage takes place in the mitochondria of the cells. ATP is produced from conversion of pyruvate to acetylCoA in a process called the Citric Acid Cycle.
Option B, Bronze is made of the metals copper and tin.
Alloys are essentially materials that consist of two or more metal elements.
-T.B.
