1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Makovka662 [10]
2 years ago
7

At the end of chemical reactions, what is the total mass of the reactants compared to the total mass of the products?

Chemistry
1 answer:
zhuklara [117]2 years ago
5 0
Mass is never lost or gained in chemical reactions. We say that mass is always conserved. In other words, the total mass of products at the end of the reaction is equal to the total mass of the reactants at the beginning. This is because no atoms are created or destroyed during chemical reactions.
You might be interested in
A sample of the mineral hematite Iron (III) oxide has a mass of 12.4g. How many moles of the mineral are present?
8090 [49]

Thus problem is providing us with the mass of iron (III) oxide as 12.4 g so the moles are required and found to be 0.0776 mol after the calculations:

<h3>Mole-mass relationships:</h3>

In chemistry, we use mole-mass relationships in order to calculate grams from moles and vice versa. In this case, since we are given the mass of iron (III) oxide as 12.4 g one can calculate the moles by firstly quantifying its molar mass:

Fe_2O_3\rightarrow 2*55.85 g/mol+3*16.00 g/mol=159.7g/mol

Then, we prepare a conversion factor in order to cancel out the grams and thus, get moles:

12.4gFe_2O_3*\frac{1molFe_2O_3}{159.7gFe_2O_3} \\\\=0.0776molFe_2O_3

Learn more about mole-mass relationships: brainly.com/question/18311376

8 0
2 years ago
Why can't all mixtures be classified as solutions?
shusha [124]
D. Not all mixtures are heterogeneous
7 0
3 years ago
Will a precipitate of magnesium fluoride form when 300. mL of 1.1 × 10 –3 M MgCl 2 are added to 500. mL of 1.2 × 10 –3 M NaF? [K
Tju [1.3M]

Answer:

No precipitate is formed.

Explanation:

Hello,

In this case, given the dissociation reaction of magnesium fluoride:

MgF_2(s)\rightleftharpoons Mg^{2+}+2F^-

And the undergoing chemical reaction:

MgCl_2+2NaF\rightarrow MgF_2+2NaCl

We need to compute the yielded moles of magnesium fluoride, but first we need to identify the limiting reactant for which we compute the available moles of magnesium chloride:

n_{MgCl_2}=0.3L*1.1x10^{-3}mol/L=3.3x10^{-4}molMgCl_2

Next, the moles of magnesium chloride consumed by the sodium fluoride:

n_{MgCl_2}^{consumed}=0.5L*1.2x10^{-3}molNaF/L*\frac{1molCaCl_2}{2molNaF} =3x10^{-4}molMgCl_2

Thus, less moles are consumed by the NaF, for which the moles of formed magnesium fluoride are:

n_{MgF_2}=3x10^{-4}molMgCl_2*\frac{1molMgF_2}{1molMgCl_2}=3x10^{-4}molMgF_2

Next, since the magnesium fluoride to magnesium and fluoride ions is in a 1:1 and 1:2 molar ratio, the concentrations of such ions are:

[Mg^{2+}]=\frac{3x10^{-4}molMg^{+2}}{(0.3+0.5)L} =3.75x10^{-4}M

[F^-]=\frac{2*3x10^{-4}molMg^{+2}}{(0.3+0.5)L} =7.5x10^{-4}M

Thereby, the reaction quotient is:

Q=(3.75x10^{-4})(7.5x10^{-4})^2=2.11x10^{-10}

In such a way, since Q<Ksp we say that the ions tend to be formed, so no precipitate is formed.

Regards.

6 0
3 years ago
A sample of nitrogen gas, (N2), occupies 45.0 mL at 27.00∘C and 80.0 kPa. What will be the pressure if the gas is cooled to −73.
maxonik [38]

Answer:

The new pressure is 53.3 kPa

Explanation:

This problem can be solved by this law. when the volume remains constant, pressure changes directly proportional as the Aboslute T° is modified.

T° increase → Pressure increase

T° decrease → Pressure decrease

In this case, temperature was really decreased. So the pressure must be lower.

P₁ / T₁ = P₂ / T₂

80 kPa / 300K =  P₂/200K

(80 kPa / 300K) . 200 K = P₂ →  53.3 kPa

6 0
3 years ago
How does 2 Na (s) + Cl2 (g) = NaCl (s) represent the coefficient in the chemical equation
Elenna [48]

Answer:

The 2 would be placed in front of the reactant Na and in front of the product NaCl

2Na + Cl2 = 2NaCl

Explanation:

This is because the ratio of elements needs to be balanced on both sides.

On the reactants side, there are 2 Na molecules and 2 Cl molecules

On the products side, there are 2 Na molecules and 2 Cl molecules

So, now the equation is balanced

3 0
2 years ago
Other questions:
  • Iki indicator tests for the presence of which substance? benedict's reagent tests for the presence of which substance?
    9·1 answer
  • Can someone help? this is hard .​
    13·1 answer
  • If the pressure of a gas is 100 kPa when the volume is measured to be 500 mL. What pressure would need to be exerted to have the
    12·1 answer
  • Energy must be removed from a liquid to change it to a solid true or false please hurry it’s a emergency
    10·2 answers
  • What is the percent yield of either if 1.11L(d=0.7134 g/mL) is isolated from the reaction of 1.500L of C2H5OH
    5·1 answer
  • An enzyme reduces the energy necessary to start a chemical reaction. This means the rate of reaction will
    8·1 answer
  • 3c reaction time =138.5 sec reation rate=
    5·1 answer
  • If the pH of a solution is 8.45, what is the concentration of the OH-?
    9·1 answer
  • A radioactive substance has a half-life of 5 million years. What is the age of a rock in which 25% of the original radioactive a
    8·1 answer
  • Can a chemical reaction take place without enzyme​
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!