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3 years ago

How was the periodic law rearranged to become the periodic table, and what is its purpose?

Chemistry

1 answer:

alexandr402 [8]3 years ago

7 0

Answer:

At earlier times elements were arrangrd on the basis of their atomic masses to study their properties easily but there were various problems like isotopes needs different position in perodic table.

After discovery of atomic number modern periodic table was created on the basis of atomic number (number of proton) that is unique for each element and varies regularly. So study of a group of elements is much easier than each element seperately that is why modern periodic table was formed.

Explanation:

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WHAT IS NORMAL MUSCLE PH

larisa [96]

The skeletal muscle ph is typically 7.15

8 0

3 years ago

Certain compound contains 7.3% carbon, 4.5% hydrogen, 36.4% oxygen, and 31.8% nitrogen. It’s reality molecular mass is 176.0. Fi

erastovalidia [21]

Answer:

The answer to your question is:

Explanation:

Data

carbon 7.3% = 7.3g

hydrogen 4.5% = 4.5g

oxygen 36.4% = 36.4 g

nitrogen 31.8% = 31.8 g

Now

For carbon

12 g --------------------1 mol

7.3 g ------------- x

x = 7.3/12 = 0.608 mol

For hydrogen

1 g -------------------- 1 mol

4.5 g ------------------ x

x = 4.5 mol

For oxygen

16 g ------------------- 1 mol

36.4 g ---------------- x

x = 2.28 mol

For nitrogen

14 g ---------------- 1 mol

31.8 g --------------- x

x = 2.27 mol

Now divide by the lowest result, the is 0.608 from carbon

carbon 0.608/0.608 = 1

hydrogen 4.5/ 0.608 = 7.4

oxygen 2.28/0.608 = 3.75

nitrogen 2.27/0.608 = 3.73

Empirical formula = CH₇O₄N₄

6 0

3 years ago

An organic compound was extracted into dichloromethane and then the aqueous layer is shaken with saturated sodium chloride solut

Ilya [14]

Answer: option A. to decrease the solubility of the organic product in water

Explanation: sodium chloride solution act as a drying agent to remove water from an organic compound that is in solution. The salt water works to pull the water from the organic layer to the water layer,therby decreasing

6 0

4 years ago

What is the difference between concentrated acid and a weak one?

makkiz [27]

Answer:

Difference between concentrated acid and weak acid :---

According to Arrhenius's theory the substances which easily get dissociated into H+ ions when dissolved in water are acids.

And the substance which readily gives H+ ions on dissociation (when dissolved in water) are Strong Acid. Examples are HCl , H2SO4 etc.

While,

Concentration of acid is just the value of pH. pH is the measurement of concentration of acid or base. The lower the pH, higher the concentration.

So strong acid is strong because it gives H+ ions readily in water and Concentration is the value of pH.

7 0

3 years ago

A chemist dissolves of pure hydroiodic acid in enough water to make up of solution. Calculate the pH of the solution. Be sure yo

Gre4nikov [31]

Answer:

1.76

Explanation:

There is some info missing. I think this is the original question.

<em>A chemist dissolves 660.mg of pure hydroiodic acid in enough water to make up 300.mL of solution. Calculate the pH of the solution. Be sure your answer has the correct number of significant digits.</em>

<em />

Step 1: Calculate the molarity of HI(aq)

M = mass of solute / molar mass of solute × liters of solution

M = 0.660 g / 127.91 g/mol × 0.300 L

M = 0.0172 M

Step 2: Write the acid dissociation reaction

HI(aq) ⇄ H⁺(aq) + I⁻(aq)

HI is a strong acid, so [H⁺] = 0.0172 M

Step 3: Calculate the pH

pH = -log [H⁺]

pH = -log 0.0172

pH = 1.76

5 0

4 years ago