Pollution comes from many small sources.

Why is combustion of fuel necessary for heat engines to do work?

azamat

Because during combustion reaction, heat energy is released and it's this energy that is converted to work

6 0

2 years ago

Compare 1 mole of H2, 1 mole of O2, and 1 mole of F2. (a) Which has the largest number of molecules? Explain why. (b) Which has

AURORKA [14]

a) Answer:

Number of molecules in 1 mole

Explanation:

a) Whether we take any of the substance among all three of the given substances they will have the same number of molecules in 1 mole of the substance is considered and the value for this will be $6.023 x 10^23$

b) Answer:

In the given question mass of the substance which is greatest is asked for one mole and we also know that mass of one mole is given by molar mass.

Explanation:

b) It is known that $31.98g/mol$ is the molar mass for oxygen which is greater than that of hydrogen while fluorine has a molar mass of $38.0 g/mol$ which on comparison shows that, it is the highest amongst all three.

3 0

2 years ago

To determine the age of fairly recent fossils and organic artifacts, it is possible to analyze the amounts of the isotopes 14C a

dolphi86 [110]

Answer: The net change in the atoms is the conversion of a neutron to a proton, turning Carbon (6 protons) into Nitrogen (7 protons).

Explanation:

Carbon-14, generated from the atmosphere, has 6 protons and 8 neutrons. That's where the 14 comes from, called the mass number, is the sum of protons and neutrons (6+8=14).

Carbon-14 is radioactive and decays by beta decay. That means one of its neutrons spontaneously turns into a proton, an electron, and a neutrino, according to:

$^{14} C \rightarrow\ ^{14} N\ +\ e^- +\ neutrino$

After that, the atom has 7 protons and 7 neutrons, maintaining its mass number but changing its atomic number from 6 to 7, turning into Nitrogen.

3 0

3 years ago

The ion formed by an atom of sulfur when it gains two electrons is called a:

dolphi86 [110]

Answer:

sulfide ion

Explanation:

however, when non-metalic elements gain electrons to form anions the end of their name is change to "-ide".foe example, a flourin atom gains one electronto become a flouride ion(F`) and sulfur gains two electrons to become a sulfide ion(s^2)

8 0

2 years ago

Arrange the following chloroarenes in increasing order of their reactivity in nucleophilic substitution to form their correspond

pantera1 [17]

The question is incomplete. Complete question is attached below
..............................................................................................................................

Correct Answer: Option C i.e. I ~ III < IV < V < II

Reason:
During a nucleophilic subsitution reaction of chloroarenes, Cl- group is replaced by an nucleophile like OH-.

Order of reactivity, during such reactions depends on the electron density on carbon atom that is attached to Cl. Lower the electron density, greater will be the reactivity.

Among the provided chloroarenes, electron density on C atom will be minimum in case of compound II, because of presence of electron withdrawing group (-NO2) at ortho and para position. Due to this, there will be large number of resonating structures. This signifies greater electron de-localization, and hence largest reactivity for nucleophilic substitution reaction.

Followed by this, compound V will show greater reactivity, due to presence of -NO2 group at para and one of the ortho position. Compound IV will have less number of resonating structures as compared to compound II and V, hence it will display poor reactivity towards nucleophilic substitution reaction.

Finally, compound 1 and III will minimum reactivity towards nucleophilic substitution reaction, because -NO2 group present at meta position (compound III) will not participate in resonance.

6 0

2 years ago