Answer:
35 amu
Explanation:
In an atom, only masses of protons and neutrons are relevant. electrons are so small in size that their masses are negligible.
The mass of 1 proton/neutron is 1amu.
Answer:
When two substances having different temperatures are introduced or kept together, heat energy, Q, flows from a substance at higher temperature to a substance at lower temperature. Also, heat continues to be transferred until their temperatures are equalized, at which point the substances are in thermal equilibrium. In a closed system, the amount of energy lost is equal to but opposite the amount of energy gained.
Explanation:
Answer:
The main competing reaction when a primary alkyl halide is treated with alcoholic potassium hydroxide is SN2 substitution.
Explanation:
The relative percentage of products of the reaction between an alkyl halide and alcoholic potassium hydroxide generally depends on the structure of the primary alkylhalide. The attacking nucleophile/base in this reaction is the alkoxide ion. Substitution by SN2 mechanism is a major competing reaction in the elimination reaction intended.
A more branched alkyl halide will yield an alkene product due to steric hindrance, similarly, a good nucleophile such as the alkoxide ion may favour SN2 substitution over the intended elimination (E2) reaction.
Both SN2 and E2 are concerted reaction mechanisms. They do not depend on the formation of a carbocation intermediate. Primary alkyl halides generally experience less steric hindrance in the transition state and do not form stable carbocations hence they cannot undergo E1 or SN1 reactions.
SN2 substitution cannot occur in a tertiary alkyl halides because the stability of tertiary carbocations favours the formation of a carbocation intermediate. The formation of this carbocation intermediate will lead to an SN1 or E1 mechanism. SN2 reactions is never observed for a tertiary alkyl halide due to steric crowding of the transition state. Also, with strong bases such as the alkoxide ion, elimination becomes the main reaction of tertiary alkyl halides.
Answer: 3 oxygen atoms!
Explanation: Let me know if I'm wrong, if not I'm happy to help!
Answer:
The element belongs to group 15 of the present periodic table
Explanation:
Isotopes have the same proton number, what differs is that they have different number of neutrons.
Now since the half-sum of their neutrons is 19, the total number of neutrons would be 19 * 2 = 38 neutrons.
Also, their masses add up to be 68, since the total mass equals sum of neutrons and sum of protons, this means that the total number of protons is 68-38 = 30
Since this is equal in both isotopes, this means that the proton number of the element is 30/2 = 15
The atomic number is the number of protons in the nucleus of an atom. Since the atomic number is 15, this element is phosphorus and it belongs to group 15 of the present periodic table