All categories

4 years ago

Not sure how to do this

Chemistry

1 answer:

faust18 [17]4 years ago

4 0

Answer:

0.0991 M

Explanation:

Step 1: Write the neutralization reaction between oxalic acid and sodium hydroxide.

H₂C₂O₄ + 2 NaOH = Na₂C₂O₄ + 2 H₂O

Step 2: Calculate the moles of oxalic acid

The molar mass of H₂C₂O₄ is 90.03 g/mol. The moles corresponding to 153 mg (0.153 g) are:

$0.153g \times \frac{1mol}{90.03g} = 1.70 \times 10^{-3} mol$

Step 3: Calculate the moles of sodium hydroxide

The molar ratio of H₂C₂O₄ to NaOH is 1:2.

$1.70 \times 10^{-3} molH_2C_2O_4 \times \frac{2molNaOH}{1molH_2C_2O_4} = 3.40 \times 10^{-3} molNaOH$

Step 4: Calculate the molarity of sodium hydroxide

$\frac{3.40 \times 10^{-3} mol}{34.3 \times 10^{-3} L} = 0.0991 M$

You might be interested in

A student who is performing this experiment pours an 8.50 mL sample of the saturated borax solution into a 10 mL graduated cylin

gtnhenbr [62]

Answer:

ksp = 0,176

Explanation:

The borax (Na₂borate) in water is in equilibrium, thus:

Na₂borate(s) ⇄ borate²⁻(aq) + 2Na⁺(aq)

When you add just borax, the moles of Na²⁺ are twice the moles of borate²⁻, that means 2borate²⁻=Na⁺ (1)

The ksp is defined as:

ksp = [borate²⁻] [Na⁺]²

Then, borate²⁻(B₄O₇²⁻) reacts with HCl thus:

B₄O₇²⁻ + 2HCl + 5H₂O → 4H₃BO₃ + 2Cl⁻

The moles of HCl that reacts with B₄O₇²⁻ are:

0,500M×0,01200L = 6,00x10⁻³ mol of HCl

As two moles of HCl react with 1 mol of B₄O₇²⁻, the moles of B₄O₇²⁻ are:

6,00x10⁻³ mol of HCl× $\frac{1molB_{4}O_{7}^{2-}}{2molHCl}$ = 3,00x10⁻³ mol of B₄O₇²⁻

For (1), moles of Na⁺ are 3,00x10⁻³ mol ×2 = 6,00x10⁻³ mol of Na⁺

The [borate²⁻] is 3,00x10⁻³ mol of B₄O₇²⁻/0,00850L = 0,353M

And [Na⁺] is 6,00x10⁻³ mol of Na⁺ / 0,00850L = 0,706M

Replacing in the expression of ksp:

ksp = [0,353] [0,706]²

ksp = 0,176

I hope it helps!

8 0

3 years ago

When the following equation is balanced, what is the coefficient for O2?

harkovskaia [24]

Answer:

3 is the coefficient of oxygen.

Explanation:

Chemical equation:

CH₃OH + O₂ → CO₂ + H₂O

Balanced chemical equation:

2CH₃OH + 3O₂ → 2CO₂ + 4H₂O

The given reaction is combustion reaction. In this reaction methanol is burn in the presence of oxygen and produces carbon dioxide and water.

The balance equation show reaction also follow the law of conservation of mass.

This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.

4 0

3 years ago

What is the mass number of an atom that contains 12 protons, 14 neutrons, and 12 electrons? *

Yuri [45]

The mass number of an atom : 26

<h3>Further explanation</h3>

Given

12 protons, 14 neutrons, and 12 electrons

Required

The mass number

Solution

Inside the atom there are 3 sub-particles, namely protons, neutrons and electrons. Protons and electrons are present in the atomic nucleus while electrons move around the atomic nucleus through energy levels in the atomic shell

Atomic number = number of protons = number of electrons

Mass number = number of protons + number of neutrons

Input the value :

Mass number = 12 + 14

Mass number = 26

7 0

3 years ago

This is chemistry: 2 questions having to do with particles

PilotLPTM [1.2K]

Answer 1 :

Image 1 shows : Liquid phase

Image 2 shows : Gas phase

Image 3 shows : Solid phase

Image 4 shows : Solid phase

Solid phase : In this state, the molecules are closely and tightly packed. There is no vacant space present in it.

Liquid phase : In this state, the molecules are loosely packed and there is an intermediate vacant space present in it.

Gas phase : In this state, the molecules are very loosely packed and there is a lot of vacant space present in it.

Answer 2 :

Liquid to gas : Evaporation

Solid to gas : Sublimation

Gas to solid : Deposition

Solid to liquid : Melting

Liquid to solid : Freezing

Gas to liquid : Condensation

Explanation :

Evaporation : It is a type of vaporization process in which a liquid changes into gas phase by providing heat.

Sublimation : It is a process in which a solid changes directly into gas phase without passing through a liquid phase.

Deposition : It is a process in which a gas transforms directly into a solid phase without passing through a liquid phase.

Melting : It is a process in which a solid changes into liquid phase by providing heat.

Freezing : It is a process in which a liquid transform into a solid phase.

Condensation : It is a process in which a water vapor(gas) changes into liquid state.

6 0

3 years ago

What's Hexane density in g/cm^3 not g/mL

horrorfan [7]

1 cm^3 and 1 mL are equivalent... so g/cm^3 is the same as g/mL

7 0

3 years ago