Answer:
For any given isotope, the sum of the numbers of protons and neutrons in the nucleus is called the mass number. This is because each proton and each neutron weigh one atomic mass unit. By adding together the number of protons and neutrons and multiplying by 1, you can calculate the mass of the atom.
Equilibrium occurs when forward and reverse directions of a reversible reaction occur at the same rate so there is no overall change in the amounts of reactants and products.
Answer/Explanation
Characteristics of Life Present in Viruses:
- has a defined boundary - viruses are made up simply of genetic material surrounded by a<u> protein capsid </u>and sometimes a lipid membrane
Characteristics of Life Absent in Viruses:
- made up of one or more cells - one of the main arguments for why viruses are not living is that they are <u>not cellular</u>
- uses energy - this is a tricky one. They don't use or produce their own energy. However, in order to reproduce they do hijack the host cells and <u>steal energy</u> from them in order to reproduce
- exhibits growth and development - although viruses do <u>reproduce</u>, the individual viral particles do not exhibit growth or development
- possess internal organisation - other than the fact they ahve genetic material, the inside of a virus does not contain internal organization like a cytosol, instead conssiting of the bare minimum amount of proteins to survive
- eliminates waste - since they do not have their own metabolism, they have no waste to eliminate
A stock solution is a solution of a known concentration. Stock solution has a high concentration and therefore, the known amount of stock solution is used for preparing different concentrations, by diluting the same with the known amount of the solvent being used, such as water.
F. <em>None of the above
</em>
<em>No O atoms are present</em> as reacting substances, only O_2 and H_2O molecules.
O_2 + 2H_2O + 2e^(-) → 4OH^(-)
We must use <em>oxidation numbers</em> to decide whether oxygen or water is the substance reduced.
The oxidation number of O changes from 0 in O_2 to -2 in OH^(-).
A decrease in oxidation number is <em>reduction</em>, so O_2 is the substance reduced.
The oxidation number of O is -2 in both H_2O and OH^(-), so water is <em>neither oxidized nor reduced</em>.