<u>Analysing the Question:</u>
We are given a 250 mL solution of 0.5M K₂Cr₂O₇
Which means that we have:
0.5 Mole in 1L of the solution
0.125 moles in 250 mL of the solution <em>[dividing both the numbers by 4]</em>
<em />
<u>Mass of K₂Cr₂O₇ in the given solution:</u>
Molar mass of K₂Cr₂O₇(Potassium Dichromate) = 194 g/mol
<em>we know that we have 0.125 moles in the 250 mL solution provided</em>
Mass = Number of moles * Molar mass
Mass = 0.125 * 194
Mass = 36.75 grams
Luster is the term- means the shininess of the metal
Answer: a. +2, cation and magnesium ion .
b. -1, anion, chloride
c. -2, anion, oxide
d. +1. cation , potassium ion
Explanation:
When an atom accepts an electron negative charge is created on atom and is called as anion.
When atom loses an electron positive charge is created on atom and is called as cation.
Magnesium (Mg) with atomic number of 12 has electronic configuration of 2,8,2 and thus it can lose 2 electrons to form 
cation and becomes magnesium ion.
Chlorine (Cl) with atomic number of 17 has electronic configuration of 2,8,7 and thus it can gain 1 electron to form 
anion and becomes chloride.
Oxygen (O) with atomic number of 8 has electronic configuration of 2,6 and thus it can gain 2 electrons to form 
anion and becomes oxide.
Potassium (K) with atomic number of 19 has electronic configuration of 2,8,8,1 and thus it can lose 1 electron to form 
cation and becomes potassium ion.
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.
