31
A dalton is the same as an atomic mass unit. And an atomic mass unit is approximately the mass of a nucleon (proton or neutron) such that the mass is 1 g/mol. So in this problem you have 15 protons and 16 neutrons, so the number of daltons is 15 + 16 = 31.
Answer:
Explanation:
In the qualitative analysis of metal salts , we see that in group I , metal chlorides are precipitated out . It is so because their metal chlorides are insoluble in water .
In this group following metal ions are present
Ag+,
Hg₂²⁺
Pb²⁺
Answer:
When iron is heated in air it reacts with oxygen to form the compound iron oxide. Iron is a solid and oxygen is a gas. 5 Draw diagrams to show how the atoms are arranged in iron, oxygen and iron oxide in the circles below their names. Use different colours for the iron atoms and the oxygen atoms.
Explanation:
Physical change is the change we can see with our eyes. Chemical change is the change that we cannot see. Examples: physical change: The Polar ice caps are melting, and we can see that as it happens. Chemical change: The cooking of an egg or some combustion, like a fire. We can't see the chemicals coming from the fire, but there are chemicals coming from what is being burned and is being released into the air that we cannot see.
Answer:
Option d.
Explanation:
Ketones contain a carbonyl groups as a functional group, which is a carbon bonded to oxygen with a double bond. In a ketone, the carbon is always bonded to two carbon atoms:
R-C(=O)-R'
The carbon in the carbonyl group has a hybridization sp2 (3 hybrid orbitals with an unhybridized p orbital), where two of the orbitals form sigma (σ) bonds with the other two carbons (R-C-R') and the other hybrid orbital form a sigma bond with the oxygen (C-O). The unhybridized p orbital on the carbon atom is used to form a pi (π) bond with the oxygen, thus forming the double bond (C=O).
The bond of a carbonyl group is polar, because of the difference of the electronegativity between the carbon atom and the oxygen atom.
Hence, from all of the above <u>we can discard the option a</u>, (the carbonyl groups exhibits sp2 hybridization), <u>the option b</u> (carbon-oxygen bond is a bond polar) and <u>the option c</u> (the group must always be in the middle of a carbon chain, the groups that are always in the end, are a aldehyde groups).
Therefore, the correct option is d, the functional group of this type of compound must always be in the middle of a carbon chain.
I hope it helps you!
