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3 years ago

Which chemical equation shows that the total mass during a chemical reaction stays the same?

Chemistry

2 answers:

k0ka [10]3 years ago

5 0

Answer:

Option A) Mg + Cl₂ → MgCl₂

Explanation:

The law of conservation of mass is guaranteed in a chemical equation. Since the mass of the atoms do not change, that means that the number of each kind of atoms in the reactant side is equal to the number of atoms of the same kind in the product side.

The first equation is:

A) Mg + Cl₂ → MgCl₂

Number of atoms:

atom Reactant side Product side

Mg 1 1

Cl 2 2

Therefore, the table displays that there are the same number of atoms of each kind on both sides, showing that the total mass during the chemical reaction stays the same.

B) NaOH + MgCl₂ → NaCl + MgOH

This equation displays 2 atoms of Cl on the left side and 1 atom of Cl on the right side; thus, it is not showing that the total mass stays the same during the chemical reaction.

C) 2Na + 2H₂O → NaOH + H₂

Neither the sodium, nor oxygen, nor hydrogen atoms are balanced. Thus, this does not show that the total mass stays the same.

D) H₂O + O₂ → H₂O

The reactant side contains 3 oxygen atoms and the product side contains 1 atoms of oxygen; thus, this is not balanced: it does not show that the total mass stays de same during the chemical reaction.

Triss [41]3 years ago

4 0

Answer:

Explanation:

Mg + Cl2 → MgCl2 obeys the law of conservation of mass since the same number of each type of atom appears on both sides of the reaction.

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Polymerization starts at the ________ end of the template.

balandron [24]

Answer:

B. 3'

Explanation:

Polymerization is the process of forming large molecules by joining together many small molecules. The small molecules are known as the monomers, and the macromolecules are called polymers.

There are two(2) types of polymerization.

a. addition polymerization

b. condensation polymerization

Polymerization is characterized by eliminating small molecules such as water, carbon(IV)oxide, methanol e.t.c.

In complex compounds, polymerization starts at the 3' end of the template.

3 0

3 years ago

100x100 wsbntxrdfdmxnjhdtnvj

CaHeK987 [17]

Answer:

10000

Explanation:

just add the zeros

hope dis helps ^-^

6 0

3 years ago

Read 2 more answers

If 97.7 ml of silver nitrate solution reacts with excess potassium chloride solution to yield 0.326 g of precipitate, what is th

BlackZzzverrR [31]

The complete balanced chemical reaction is written as:

AgNO3 + KCl ---> AgCl + KNO3

where AgCl is our precipitate

So calculating for moles of AgCl produced: MM AgCl = 143.5 g/mol

moles AgCl = 0.326 g / (143.5 g/mol) = 2.27 x 10^-3 mol

we see that there is 1 mole of Ag per 1 mole of AgCl so:

moles Ag = 2.27 x 10^-3 mol

The molarity is simply the ratio of number of moles over volume in Liters, therefore:

Molarity = 2.27 x 10^-3 mol / 0.0977 L

Molarity = 0.0233 M

4 0

3 years ago

A helium-filled balloon has a volume of 2.48 L and a pressure of 150 kPa. The volume of the balloon increases to 2.98 L after yo

Tema [17]

Answer:

THE NEW PRESSURE OF THE HELIUM GAS AT 2.98 L VOLUME IS 124.8 kPa.

AT AN INCREASE ALTITUDE, THERE IS A LOWER PRESSURE ENVIRONMENT AND THE HELIUM GAS PRESSURE DECREASES AND HENCE AN INCREASE IN VOLUME.

Explanation:

The question above follows Boyle's law of the gas law as the temperature is kept constant.

Boyle's law states that the pressure of a fixed mass of gas is inversely proportional to the volume, provided the temperature remains constant.

Mathematically, P1 V1 = P2 V2

P1 = 150 kPa = 150 *10^3 Pa

V1 = 2.48 L

V2 = 2.98 L

P2 = ?

Rearranging the equation, we obtain;

P2 = P1 V1 / V2

P2 = 150 kPa * 2.48 / 2.98

P2 = 372 *10 ^3 / 2.98

P2 = 124.8 kPa.

The new pressure of the gas when at a height which increases the volume of the helium gas to 2.98 L is 124.8 kPa.

6 0

3 years ago

Claims · Evidence • Reasoning A student

sashaice [31]

As with the properties of a substance, the changes that substances undergo can be classified as either physical or chemical. During physical changes a substance changes its physical appearance, but not its composition. The evaporation of water is a physical change.

(I searched that up but here’s an explanation with my own words that you can use):

Change in matter can be classified as a physical change as well as a chemical change due to the properties of substance. A physical change changes substance within its appearance but not its composition. For an example: The evaporation of water is a physical change.

There you go hopefully that helped

3 0

3 years ago