Which chemical equation follows the law of conservation of matter?
A
2K + Ca(NO3)2 → K(NO3) + Ca

B
C5H12 + 7O2 → 5CO2 + 6H2O

C
GaF3 + 3Cs → 3CsF + Ga

D
2VCl2 + H2 → 2HCl + V

Equation C  follows the law of conservation

GaF3 + 3Cs → 3CsF + Ga

Explanation:

Step 1: Data given

The law of conservation of matter states that in any given system that is closed to the transfer of matter, the amount of matter in the system stays constant . This means, in chemical reactions, the total mass of the products must equal the total mass of the reactants.

A

2K + Ca(NO3)2 → K(NO3) + Ca

In this equation, we have 2x K on the left side, but only 1x K on the right side (in KNO3). We have 2x NO3 on the left side (in Ca(NO3)2 ) but only 1x NO3 on the right side (in KNO3). The amount is not the same on both side, so doesn't follow the law of conservation of matter

The correct equation would be 2K + Ca(NO3)2 → 2K(NO3) + Ca

B

C5H12 + 7O2 → 5CO2 + 6H2O

In this equation we have 14x O atoms on the left side, but 16x O atoms on the right side (10x O in 5CO2 and 6x O in 6H2O). This means we have more O- atoms in products than in the reactants. The amount is not the same on both side, so doesn't follow the law of conservation of matter

The correct equation would be C5H12 + 8O2 → 6H2O + 5CO2

C

GaF3 + 3Cs → 3CsF + Ga

In this equation we have the same amount in reactants as in products.

This equation follows the law of conservation

D

2VCl2 + H2 → 2HCl + V

On the left side we have 2x V (in 2VCl2), on the right side we have 1x V. The amount is not the same on both side, so doesn't follow the law of conservation of matter

The correct equation would be VCl2 + H2 → 2HCl + V

thats how its supposed to be

most historians agree that gabriel mouton, the vicar of st. paul’s church in lyons, france, is the “founding father” of the metric system. he proposed a decimal system of measurement in 1670. mouton based it on the length of one minute of arc of a great circle of the earth (now called a nautical mile, 1852 meters). he also proposed the swing-length of a pendulum with a frequency of one beat per second as the unit of length (about 25 cm). a pendulum beating with this length would have been fairly easy to produce, thus facilitating the widespread distribution of uniform standards. over the years, his work was revised, improved, and extended by a number of french scientists.

the political sponsor of weights and measures reform in the french revolutionary national assembly was the bishop of autun, better known as talleyrand. under his auspices, the french academy appointed several committees to carry out the work of developing a usable system of weights and measures for france. one of the committees recommended a decimalized measurement system based upon a length equal to one ten-millionth of the length of a quadrant of the earth’s meridian (i.e., one ten-millionth of the distance between the equator and the north pole).