All categories

3 years ago

The quinine in tonic water shines a strange blue-white colour when lit with UV light. Explain what is happening here.

Chemistry

1 answer:

Alecsey [184]3 years ago

5 0

Answer:

Here's what I get.

Explanation:

Quinine contains phosphors, substances that glow when they are hit with certain wavelengths of light.

The phosphors in quinine absorb UV light, which is invisible to our eyes.

Electrons in the phosphors absorb the UV energy and are excited to higher energy levels.

When the electrons drop back to lower energy levels, they emit some of this energy as a glowing blue visible light.

You might be interested in

How would the law of conservation of energy apply to a backup generator

Karo-lina-s [1.5K]

The law of conservation of energy states that no energy is created nor destroyed. When using a backup generator, the generator uses energy from another resource.

4 0

2 years ago

Read 2 more answers

-What important role does chemistry play in society?

Serggg [28]

Answer:

Chemistry helps in improving the quality of our life, it helps in improving food production, building & construction, military and space science, clothing materials, medicine and transportation.

4 0

2 years ago

What is Avogadro's number, and why is it useful? (3 points)

SashulF [63]

Answer:

6.022 x 10²³; it is a conversion factor between moles and number of particles

Explanation:

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

For example,

18 g of water = 1 mole = 6.022 × 10²³ molecules of water

1.008 g of hydrogen = 1 mole of hydrogen = 6.022 × 10²³ atoms of hydrogen

238 g of uranium = 1 mole of uranium = 6.022 × 10²³ atoms of uranium

By taking ions:

62 g of NO⁻₃ = 1 mole of NO⁻₃ = 6.022 × 10²³ ions of NO⁻₃

96 g of SO₄²⁻ = 1 mole of SO₄²⁻ = 6.022 × 10²³ ions of SO₄²⁻

4 0

3 years ago

1.Calculate the molarity of a 6.15% (w/v%) sodium hypochlorite (NaOCl) solution (i.e. in a 100 ml of solution there is 6.15 gram

shtirl [24]

Answer:

C U M

Explanation:

3 0

2 years ago

Suppose of nickel(II) chloride is dissolved in of a aqueous solution of potassium carbonate. Calculate the final molarity of chl

stich3 [128]

Answer: Molarity of chloride anion = 0.32 M

<em>Note: the question is missing some values. The full question is given below;</em>

<em>Suppose 7.26 g of nickel(II) chloride is dissolved in 350 mL of a 0.50 M aqueous solution of potassium carbonate. Calculate the final molarity of chloride anion in the solution. You can assume the volume of the solution doesn't change when the nickel(II) chloride is dissolved in it. Be sure your answer has the correct number of significant digits.</em>

Explanation:

Molarity or molar concentration is the number of moles (mol) of component per volume (liters) concentration of solution in mol/L or M

The mass of nickel (II) chloride is 7.26 g.

The volume of potassium carbonate is 350 mL = 0.35 L

The molarity of potassium carbonate solution is 0.50 M

The reaction of nickel (II) chloride and potassium carbonate is given below.

NiCl₂(aq) + KCO₃(aq) --------> KCl(aq) +NiCO₃(s)

The dissociation of nickel (II) chloride is given below.

NiCl₂ -----> Ni²⁺ + 2Cl⁻

The molar mass of nickel (II) chloride is 129.6 g/mol

The moles of nickel (II) chloride can be calculated by the formula given below;

No of moles = mass(g) / molar mass (g/mol)

No of moles = 7.26 / 129.6 = 0.056 moles

Therefore, molarity of NiCl₂ = 0.056 moles/ 0.35 L = 0.16 M

The molarity of 1 mole nickel (ii) chloride is 0.16 m and according to dissociation of nickel (II) chloride, 1 mole of nickel (II) chloride gives 2 moles of chloride anion.

Therefore, the molarity of chloride anion = 0.16 * 2 = 0.32 M

3 0

3 years ago