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3 years ago

What event brought the universe into existence

Chemistry

2 answers:

ss7ja [257]3 years ago

7 0

The big bang; that's what most scientists think.

Dennis_Churaev [7]3 years ago

7 0

The event that brought the universe into existence is "The Big Bang," it is really just a theory that says the universe was created by an explosion or "bang."

You might be interested in

Convert 3 moles of h2o into grams

lilavasa [31]

To convert 3 mol H2O to grams, just multiply by the molar mass of H2O.

3 mol H2O * 18 g H2O / 1 mol H2O = 54 g H2O

Hope this helped.

4 0

3 years ago

A beaker of nitric acid is neutralized with dilute aqueous solution of calcium hydroxide.Write a net ionic equation for this rea

Soloha48 [4]

Complete balanced equation: 2HNO₃ + Ca(OH)₂ → Ca(NO₃)₂ + 2H₂O

Ionized equation (with spectator ions):
2H⁺ + 2NO₃⁻ + Ca²⁺ + 2OH⁻   → Ca²⁺ + 2NO₃⁻ + 2H₂O

By eliminating the ions that are the same of both sides of the equation (spectator ions):

2H⁺ + 2OH⁻   → 2H₂O [Net Ionic Equation]

3 0

3 years ago

Read 2 more answers

Given the equation: HCl + Na2SO4 → NaCl + H2SO4, if you start with 8 moles of hydrochloric acid, how many grams of sulfuric acid

Simora [160]

Answer:

392g sulfuric acid are produced

Explanation:

Based on the balanced equation:

2HCl + Na2SO4 → 2NaCl + H2SO4

2 moles of HCl produce 1 mole of sulfuric acid

To solve the problem we need to find the moles of sulfuric acid produced based on the chemical equation. Then, using its molar mass -Molar mass H2SO4 = 98g/mol- we can find the mass of sulfuric acid produced:

Moles sulfuric acid:

8mol HCl * (1mol H2SO4 / 2mol HCl) = 4 mol H2SO4

Mass sulfuric acid:

4mol H2SO4 * (98g / mol) =

392g sulfuric acid are produced

4 0

3 years ago

Name two compounds with more exothermic lattice energies than scandium oxide and justify your choice.

N76 [4]

Answer:

1 . $Al_2O_3$

2. $TiO_2$

Explanation:

The more stable the ionic compound, the more is it lattice energy.

The more the charge on the cation and the anion, the greater is the lattice energy.
The less the size of the cation and the anion, the greater is the lattice energy.

Scandium oxide ( $Sc_2O_3$ ) is an oxide in which $Sc^{3+}$ behaves as cation and $O^{2-}$ behaves as anion.

The compounds which has higher lattice energy than scandium oxide are:

1 . $Al_2O_3$

This is because the charge are same on the cation and the anion as in the case of the Scandium oxide but the size of the cation $Al^{3+}$ is smaller than $Sc^{3+}$ . Thus, this corresponds to higher lattice energy.

2. $TiO_2$

This is because the charge on the cation $Ti^{4+}$ is greater than that of $Sc^{3+}$ and also the size of the cation $Ti^{4+}$ is smaller than $Sc^{3+}$ . Thus, this corresponds to higher lattice energy.

3 0

3 years ago

During an investigation, a student burns magnesium to form magnesium oxide. The starting mass of magnesium is measured as 21.3 g

enot [183]

Answer:

Percentage yield = 85.2%

Explanation:

Given data:

Mass of Mg = 21.3 g

Actual yield of MgO = 30.2 g

Percentage yield = ?

Solution:

Chemical equation:

2Mg + O₂ → 2MgO

Number of moles of Mg = mass/molar mass

Number of moles of Mg = 21.3 g / 24.3 g/mol

Number of moles of Mg = 0.88 mol

Now we will compare the moles of MgO with Mg.

Mg : MgO

2 : 2

0.88 : 0.88

Mass of MgO:

Mass of MgO= moles × molar mass

Mass of MgO= 0.88 mol × 40.3g/mol

Mass of MgO = 35.46 g

Actual yield of MgO = 30.2 g

Percentage yield:

Percentage yield = Actual yield/theoretical yield × 100

Percentage yield = 30.2 g/ 35.46 g × 100

Percentage yield = 85.2%

3 0

3 years ago