I don't know what the problem is, but here are some rues to help you out:
- All non-zero figures are significant
- When a zero falls between non-zero digits, that zero is significant.
- When a zero falls after a decimal point, that zero is significant.
- When multiplying and dividing significant figures, the answer is limited to the number of sig figs equal to the least number of sig figs in the problem.
- When adding and subtracting, the answer is limited to the number of decimal places in the number with the least number of decimal places.
Matter- Anything that occupies space and has mass is called matter.That is they have both mass and volume.
Apple is an example of matter because it occupies space and has mass and volume.
Explanation:
impurities affect both melting point and boiling point
in the case of melting point it lowers the melting point
so I guess one of the samples Ie contained impurities
Answer:
A) secondary amide
Explanation:
When carboxylic acid reacts with a primary amine, a condensation reaction takes place with the elimination of a water molecule .
For example, ethanol reacts with methylamine which is a primary amine gives N-Methylacetamide and a water molecule as:
The bond formed which is
O
||
-- C ---NH ---
is known as secondary amide group as only one hydrogen is attached to nitrogen atom in the amide bond.
HCl is considered as polar molecule and that is incorrect answer, The choices provided are A) HCl , B) CH₄ , C) H₂O, D) NH₃
And the correct answer is : B) CH₄
In case of H₂O and NH₃ the high difference in electronegativity between nitrogen or oxygen and hydrogen make the bonds acquire partial charges and become polar while in case of CH₄ the difference in electronegativity between carbon and hydrogen is only 0.4 so it considered as non-polar bond
also carbon connected from all directions with Hydrogens
