Answer:
1.69.
Explanation:
- The solution = 12.0 / 7.11 = 1.687 = 1.69.
- The rule of significant figures for division states that: the results are reported to the fewest significant figures.
- 12.0 contains 3 significant figures.
- 7.11 contains 3 significant figures.
So, the solution should contain 3 significant figures.
- Now, the issue id of rounding; In a series of calculations, carry the extra digits through to the final result, then round.
- If the digit to be removed is equal to or greater than 5, the preceding digit is increased by 1.
- The digit that should be removed is 7 that is larger than 5 so increase the preceding digit by 1.
Nanowhiskers or cellulose nanofibers
are nano-structured cellulose produced by bacteria. They have relatively high
crystallinity and ability to form a dense network held together by
inter-fibrillar bonds that has the tendency to act as a barrier through their
film-forming properties to which they can repel stains on fabric.
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Answer:
C. Its oxidation number increases.
Explanation:
- <em><u>Oxidation is defined as the loss of electrons by an atom while reduction is the gain of electrons by an atom</u></em>.
- Atoms of elements have an oxidation number of Zero in their elemental state.
- When an atom looses electrons it undergoes oxidation and its oxidation number increases.
- For example, <em><u>an atom of sodium (Na) at its elemental state has an oxidation number of 0. When the sodium atom looses an electrons it becomes a cation, Na+, with an oxidation number of +1 , the loss of electron shows an increase in oxidation number from 0 to +1.</u></em>
Full question options;
(Fe, Pb, Mg, or Ca)
Answer:
Iron - Fe
Explanation:
We understand tht metals pretty much form bonds by losing their valence (outermost electrons). But this question specifically asks for metals that lose beyond their outermost electrons; next to outermost principal energy levels.
Pb, Mg, and Ca only lose their outermost electrons to form the following ions;
Pb2+, Mg2+, and Ca2+.
This is because their ions have achieved a stable octet configuration - the dreamland of atoms where they are satisfied and don't need to go into reactions again.
Iron on the other hand has the following electronic configurations;
Fe: [Ar]4s2 3d6
Fe2+: [Ar]4s0 3d6
Fe3+: [Ar]4s0 3d5
This means ion can lose both the ooutermost electrons (4s) and next to outermost principal energy levels (3d). So correct option is Iron.
