Experiment That Can Be Tried At Home
Experiment#1:Sound from a record
You will need:
1:An unwanted vinyl record
2:Paper
3:Stiff cardboard
4:Round headed map pins
5:Thumb tacks
6:Sheet of Thick cardboard
7:Scissors
8:Glue, Tape
Method:
1:Tape a thumb tack point down into the record's central hole, and another pin point-up near it.
2:Put the record in the center of the cardboard sheet, so it can spin on the central pin.
3:Cut a strip of stiff cardboard About 2 by 7 inches (5 by 18 cm). With a map pin, pierce a hole an inch from each end of the strip. make the hole large enough to move into and out of it, without sticking.
4:Cut a narrow strip of cardboard, 4 inches long. Glue it on its edge around one hole to make a ring.
5:Cut a paper disk enough to cover the cardboard ring. Glue the head of a map pin to its center. When dry, glue the disk to the ring so that the pin sticks through
the hole in cardboard strip. This is the playing needle.
6:Make a paper cone from a sheet of paper. The narrow end of the cone must fit over the cardboard ring.Tape it inn place.
7:Stick a map pin onto the sheet of thick cardboard, about an inch beyond the edge of the record,with point sticking upward.
8:Place the cardboard strip so that the playing needle is on the outer edge of the record and the other hole in the cardboard strip is over this pin. Use the the upside down thumb tack near the center of the record As a handle to turn it. Listen carefully, and you will hear sounds!
1. Number of mole = Given mass/Mr or Ar
2. Volume of gas = Mass of gas/Mr of gas x Molar gas volume
3. Percentage yield = Experimental value/Theoretical value x 100
4. Percentage purity = Amount of pure substance/amount of substance x 100
5. Concentration g/dm3 = Concentration mole/dm3 x mass of 1 mole of solute
6. Number of mole of solute = Concentration in mole/dm3 x volume of solute (dm3)
7. Concentration in mole/dm3 = Amount of solute (mole)/volume of solution (dm3)
8. For Neutralization
Key: m1 = concentration in mole/dm3 of acid
v1 = volume of acid cm3
n1 = number of mole of acid
m2 = concentration in mole/dm3 of base
v2 = volume of base cm3
n2 = number of mole of base m1 x v1 = m2 x v2
n1 n2
9. n = Formula mass/molecular mass (given)
Empirical formula mass
10. n x Empirical formula = Molecular formula
Example (for 9th and 10th formula):
Q:Calculate molecular formula.
Given:
Empirical formula = CH
Formula mass = 78
Carbon (C) = 12
Hydrogen (H) = 1
Empirical formula mass = C x 1 + H x 1
= 12 + 1
= 13
n = Formula mass/molecular mass (given)
Empirical formula mass
= 78
6
= 13
n x Empirical formula = Molecular formula
13 x CH = C6H6
11. Number of mole = Number of atoms
Avogadro number of particle
12. Volume of gas = number of mole
Molar gas volume
Experiment#1:Sound from a record
You will need:
1:An unwanted vinyl record
2:Paper
3:Stiff cardboard
4:Round headed map pins
5:Thumb tacks
6:Sheet of Thick cardboard
7:Scissors
8:Glue, Tape
Method:
1:Tape a thumb tack point down into the record's central hole, and another pin point-up near it.
2:Put the record in the center of the cardboard sheet, so it can spin on the central pin.
3:Cut a strip of stiff cardboard About 2 by 7 inches (5 by 18 cm). With a map pin, pierce a hole an inch from each end of the strip. make the hole large enough to move into and out of it, without sticking.
4:Cut a narrow strip of cardboard, 4 inches long. Glue it on its edge around one hole to make a ring.
5:Cut a paper disk enough to cover the cardboard ring. Glue the head of a map pin to its center. When dry, glue the disk to the ring so that the pin sticks through
the hole in cardboard strip. This is the playing needle.
6:Make a paper cone from a sheet of paper. The narrow end of the cone must fit over the cardboard ring.Tape it inn place.
7:Stick a map pin onto the sheet of thick cardboard, about an inch beyond the edge of the record,with point sticking upward.
8:Place the cardboard strip so that the playing needle is on the outer edge of the record and the other hole in the cardboard strip is over this pin. Use the the upside down thumb tack near the center of the record As a handle to turn it. Listen carefully, and you will hear sounds!
Formulas for Chemistry (Chapter Moles)
1. Number of mole = Given mass/Mr or Ar
2. Volume of gas = Mass of gas/Mr of gas x Molar gas volume
3. Percentage yield = Experimental value/Theoretical value x 100
4. Percentage purity = Amount of pure substance/amount of substance x 100
5. Concentration g/dm3 = Concentration mole/dm3 x mass of 1 mole of solute
6. Number of mole of solute = Concentration in mole/dm3 x volume of solute (dm3)
7. Concentration in mole/dm3 = Amount of solute (mole)/volume of solution (dm3)
8. For Neutralization
Key: m1 = concentration in mole/dm3 of acid
v1 = volume of acid cm3
n1 = number of mole of acid
m2 = concentration in mole/dm3 of base
v2 = volume of base cm3
n2 = number of mole of base m1 x v1 = m2 x v2
n1 n2
9. n = Formula mass/molecular mass (given)
Empirical formula mass
10. n x Empirical formula = Molecular formula
Example (for 9th and 10th formula):
Q:Calculate molecular formula.
Given:
Empirical formula = CH
Formula mass = 78
Carbon (C) = 12
Hydrogen (H) = 1
Empirical formula mass = C x 1 + H x 1
= 12 + 1
= 13
n = Formula mass/molecular mass (given)
Empirical formula mass
= 78
6
= 13
n x Empirical formula = Molecular formula
13 x CH = C6H6
11. Number of mole = Number of atoms
Avogadro number of particle
12. Volume of gas = number of mole
Molar gas volume
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