The acceleration of a runner who accelerates from 0 m/s to 3 m/s in 12s

adell [148]

Answer:

Q₁: [HCl] = 0.075 N = 0.075 M.

Q₂: [KOH] = 7.675 mN = 7.675 mM.

Q₃: [H₂SO₄] = 0.2115 N = 0.105 M.

Q₄: The equivalence point is the point at which the added titrant is chemically equivalent completely to the analyte in the sample whereas the endpoint is the point where the indicator changes its color.

Explanation:

Q₁: If it takes 67 mL of 0.15 M NaOH to neutralize 134 mL of an HCl solution, what is the concentration of the HCl?

As acid neutralizes the base, the no. of gram equivalent of the acid is equal to that of the base.

The normality of the NaOH and HCl = Their molarity.

∵ (NV)NaOH = (NV)HCl

∴ N of HCl = (NV)NaOH / (V)HCl = (0.15 N)(67 mL) / (134 mL) = 0.075 N.

∴ The concentration of HCl = 0.075 N = 0.075 M.

Q₂: If it takes 27.4 mL of 0.050 M H₂SO₄ to neutralize 357 mL of KOH solution, what is the concentration of the KOH solution?

As mentioned in Q1, the no. of gram equivalent of the acid is equal to that of the base at neutralization.

The normality of H₂SO₄ = Molarity of H₂SO₄ x 2 = 0.050 M x 2 = 0.1 N.

∵ (NV)H₂SO₄ = (NV)KOH

∴ N of KOH = (NV)H₂SO₄ / (V)KOH = (0.1 N)(27.4 mL) / (357 mL) = 7.675 x 10⁻³ N = 7.675 mN.

∴ The concentration of KOH = 7.675 mN = 7.675 mM.

Q₃:If it takes 55 mL of 0.5 M NaOH solution to completely neutralize 130 mL of sulfuric acid solution (H₂SO₄), what is the concentration of the H₂SO₄ solution?

As mentioned in Q1 and 2, the no. of gram equivalent of the acid is equal to that of the base at neutralization.

The normality of NaOH = Molarity of NaOH = 0.5 N.

∵ (NV)H₂SO₄ = (NV)NaOH

∴ N of H₂SO₄ = (NV)NaOH / (V)H₂SO₄ = (0.5 N)(55 mL) / (130 mL) = 0.2115 N.

∴ The concentration of H₂SO₄ = 0.2115 N = 0.105 M.

Q₄: Explain the difference between an endpoint and equivalence point in a titration.

The equivalence point is the point at which the added titrant is chemically equivalent completely to the analyte in the sample whereas the endpoint is the point where the indicator changes its color.

The equivalence point in a titration is the point at which the added titrant is chemically equivalent completely to the analyte in the sample. It comes before the end point. At the equivalence point, the millimoles of acid are chemically equivalent to the millimoles of base.

End point is the point where the indicator changes its color. It is the point of completion of the reaction between two solutions.

The effectiveness of the titration is measure by the close matching between equivalent point and the end point. pH of the indicator should match the pH at the equivalence to get the same equivalent point as the end point.

6 0

3 years ago

Use the periodic table to write the electron configuration for rubidium (Rb) in noble has notation

Alexxx [7]

Answer:

Rb: [Kr] 5s

Step-by-step explanation:

Rb is element 37, the first element in Period 5.

It has one valence electron, so its valence electron configuration is 5s.

The noble gas configuration uses the symbol of the previous noble gas as a shortcut for the electron configurations of the inner electrons.

The preceding noble gas is Kr, so the electron configuration is Rb: [Kr] 5s.

4 0

4 years ago

How does pollution affect Earth Systems. ILL GIVE BRAINLIEST!!!!!!

BaLLatris [955]

Answer:

pollution causes smog

Smoke fog, or smog for short, is a type of intense air pollution.

it makes GHG wich is greenhouse gas and it makes the smog to stay inside the earth wich heats the Earth and it causes flood, storm, tornadoes, ect.

4 0

3 years ago

Convert 2.0 micrometer to centimeters and to inches

Dima020 [189]

Answer:

2x10⁻⁴cm and 7.9x10⁻⁵ inches

Explanation:

Micrometer, μm, is an unit of length. Could be related with another units of lenght as, for example:

1.0μm = 1x10⁻⁴cm

1.0μm = 3.93701x10⁻⁵ inches

That means, 2.0μm are:

2.0μm * (1x10⁻⁴cm / 1μm) = 2x10⁻⁴cm

And:

2.0μm * (3.93701x10⁻⁵ inches / 1μm) = 7.9x10⁻⁵ inches

7 0

3 years ago

Using 3 O2 molecules and 5 H2 molecules, how many water molecules can be produced? Do you have any left over?

makvit [3.9K]

Answer:

5 molecules of H₂O can be produced

0.5 molecules of O₂ did not reacted

Explanation:

The reaction is: 2H₂(g) + O₂(g) → 2H₂O (g)

Firstly we determine the limiting reactant:

2 moles of hydrogen need 1 mol of oxygen to react

We must know the moles of each.

6.02ₓ10²³ molecules is 1 mol

3 molecules are ____ 3 /6.02ₓ10²³ = 4.98×10⁻²⁴ moles O₂

5 molecules are ____ 5 / 6.02ₓ10²³ = 8.30×10⁻²⁴ moles H₂

2 moles of H₂ need 1 mol of O₂

Then 8.30×10⁻²⁴ moles of H₂ must need (8.30×10⁻²⁴ .1) / 2 = 4.15×10⁻²⁴ moles O₂. It is ok, because I have 4.98×10⁻²⁴ moles O₂. Oxygen is the reagent in excess, so the limiting is the H₂

1 moles of O₂ needs 2 moles of H₂ to react

Then, 4.98×10⁻²⁴ moles of O₂ must need (4.98×10⁻²⁴ .2) / 1 =9.96×10⁻²⁴ moles of H₂, we don't have enough H₂

So, in the reaction ratio is 2:2.

8.30×10⁻²⁴ moles of H₂ will produce 8.30×10⁻²⁴ moles H₂O

1 mol has 6.02×10²³ molecules

8.30×10⁻²⁴ must have (8.30×10⁻²⁴ . NA) = 5 molecules

The reagent in excess is the O₂. These means that there is oxygen that has not reacted.

We have 4.98×10⁻²⁴ moles O₂ and we used 4.15×10⁻²⁴ moles.

(4.98×10⁻²⁴ - 4.15×10⁻²⁴) = 0.83×10⁻²⁴ moles of oxgen hasn't reacted.

1 mol is contained by NA molecules

0.83×10⁻²⁴ moles are contained by (0.83×10⁻²⁴ . 6.02×10²³) = 0.5 molecules

6 0

3 years ago

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