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4 years ago

What are periods and groups on the periodic table?

2 answers:

8 0

Answer: The vertical columns on the periodic table are called groups or families because of their similar chemical behaviour. All the members of a family of elements have the same number of valence electrons and similar chemical properties. The horizontal rows on the periodic table are called periods.

Explanation:

mezya [45]4 years ago

4 0

Answer:

The vertical columns on the periodic table are called groups or families because of their similar chemical behavior. All the members of a family of elements have the same number of valence electrons and similar chemical properties. The horizontal rows on the periodic table are called periods.

Explanation:

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How do you prepare 500 ml of a 1.77M H2SO4 solution from an 18.0 M H2SO4 stock solution?

finlep [7]

Answer:

Molarity Problems Worksheet

M=nV n= # moles

V must be in liters (change if necessary)

1. What is the molarity of a 0.30 liter solution containing 0.50 moles of NaCl?

1.7M

2. Calculate the molarity of 0.289 moles of FeCl3 dissolved in 120 ml of solution?

2.41 M

3. If a 0.075 liter solution contains 0.0877 moles of CuCO4, what is the molarity?

1.2M

4. How many moles of NaCl are present in 600. ml a 1.55 M NaCl solution?

.930 moles

5. How many moles of H2SO4 are present in 1.63 liters of a 0.954 M solution?

1.56 molse

6. How many liters of solution are needed to make a 1.66 M solution containing 2.11 moles of KMnO4?

1.27 g

7. What volume of a 0.25 M solution can be made using 0.55 moles of Ca(OH)2?

2.2 L

For all of the problems below you will need to do a mole-mass conversion. Each problem will involve two steps.

8. What is the molarity in 650. ml of solution containing 63 grams of NaCl?

1.7 M

9. How many grams of Ca(OH)2 are needed to produce 500. ml of 1.66 M Ca(OH)2 solution?

61.5 g

10. What volume of a 0.88 M solution can be made using 130. grams of FeCl2?

1.2 L

Dilution Problems Worksheet

1. How do you prepare a 250.-ml of a 2.35 M HF dilution from a 15.0 M stock solution?

39.2 mL

2. If 455-ml of 6.0 M HNO3 is used to make a 2.5 L dilution, what is the molarity of the dilution?

1.1 M

3. If 65.5 ml of HCl stock solution is used to make 450.-ml of a 0.675 M HCl dilution, what is the molarity of the stock solution?

4.64 M

4. How do you prepare 500.-ml of a 1.77 M H2SO4 dilution from an 18.0 M H2SO4 stock solution?

Take 49.2-ml of 18.0 M H2SO4 stock solution and pour it into a 500-ml volumetric flask. Fill to the 500-ml line with distilled water to make 1.77M H2SO4 solution.

Extra Molarity Problems for Practice

1. How many moles of LiF would be required to produce a 2.5 M solution with a volume of 1.5 L?

3.75 M

2. How many moles of Sr(NO3)2 would be used in the preparation of 2.50 L of a 3.5 M solution?

8.75 M

3. What is the molarity of a 500-ml solution containing 249 g of KI?

3.00 M

4. How many grams of CaCl2 would be required to produce a 3.5 M solution with a volume of 2.0 L?

777 g

Explanation:

I've done this before

6 0

3 years ago

20.1 g of aluminum and 219 g of chlorine gas react until all of the aluminum metal has been converted to AlCl3. The balanced equ

Romashka-Z-Leto [24]

Answer:

The amount of Cl2 gas left , after the reaction goes to completion is : 139.655 grams

Explanation:

Molar mass : It is the mass in grams present in one mole of the substance.

Moles of the substance is calculated by:

$Moles=\frac{Mass}{Molar\ mass}$

$2Al(s)+3Cl_{2}(g)\leftarrow 2AlCl_{3}(g)$

According to this equation:

2 mole of Al = 3 mole of Cl2 = 2 mole of AlCl3

Molar mass of Al = 27.0 g/mol

Mass of Al = 20.1 gram

Moles of Al present in the reaction :

$Moles=\frac{Mass}{Molar\ mass}$

$Moles=\frac{20.1}{26.98}$

Moles of Al = 0.744

Similarly calculate the moles of Cl2

Molar mass of Cl2 = 71.0 g/mol

Mass = 219 gram

$Moles=\frac{Mass}{Molar\ mass}$

$Moles=\frac{219}{70.98}$

Moles of Cl2 = 3.08 moles

According to equation,

2 mole of Al reacts with = 3 mole of Cl2

1 moles of Al reacts with = 3/2 mole of Cl2

0.744 moles of Al reacts with = 3/2(0.744) moles of Cl2

= 1.116 moles of Cl2

But actually present Cl2 = 3.08 moles

Hence Al is the limiting reagent , and Cl2 is the excess reagent.

The whole Aluminium Al get consumed during the reaction.

The amount of Cl2 in excess = Total Cl2 - Cl2 consumed

Cl2 in excess = 3.08 - 1.116 = 1.964 moles

Cl2 in grams = 1.964 x 70.90 = 139.655 grams

6 0

4 years ago

How is an atomic radius measured?

Lelu [443]

Answer:

The radius of an atom can only be found by measuring the distance between the nuclei of two touching atoms, and then halving that distance.

Explanation:

4 0

3 years ago

MatroZZZ [7]

The correct answer is Reference Point

7 0

3 years ago

What is the base metric unit for measuring volume?

Strike441 [17]

The liter is the base metric unit for measuring volume

3 0

4 years ago

What are periods and groups on the periodic table?​

What are periods and groups on the periodic table?