Answer:
O a 2 in front of hydrochloric acid
Explanation:
the given reaction is :-
=》Zn + 2 HCL -> ZnCl2 + H2
since, mass can't be created or destroy, so number of hydrogen atoms in the reaction should be equal in product as in reaction.
so, there is 2 hydrogen in product hence there are two hydrogen in the reactants also.
it is showed in the reaction by putting a 2 in front of hydrochloric acid ( HCl ).
This problem is describe the mole-ratio composition of an allow composed by tin, lead and cadmium. Ratios are given as Sn:Pb 2.73:1.00 and Pb:Cd is 1.78:1.00, and we are asked to calculate the mass percent compositon of Pb in the allow.
In this case, according to the given information, it turns out possible realize that the following number of moles are present in the alloy, according to the aforementioned ratios:

Next, we calculate the masses by using each metal's atomic mass:

Thus, the mass percent composition of each metal is shown below:

So that of lead is 34.9 %.
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Tobacco juice would be your correct answer.
The correct answer is option c, that is, nucleus.
A usual atom comprises three subatomic particles, that is, the neutrons, protons, and electrons. According to Bohr's model, the majority of the mass of an atom is in the nucleus, that is, a small, dense region at the center of each atom, comprising nucleons.
The nucleons incorporate neutrons and protons. All the positive charge of an atom is found in the nucleus and arises from the protons, the neutrons are neutrally-charged, and the electrons are the negatively charged particles found outside of the nucleus.
Hi! Well the formula of kinetic energy is Ke = 0.5 x M x V^2
0.5 x 0.5 x 10^2
0.25 x 20
5 J (joule)