The
number of iron atoms in a cooking pot that has a mass of 0.500 kg can be solve
by dividing it by the mass of the iron atom.
Number
of iron atoms = ( 0.5 kg) (1000g / 1kg) ( 1 iron atom / 9.27 x 10^-23 g)
<span>Number
of iron atoms = 5.39 x 10 ^24 iron atoms</span>
Explanation:
It is known that efficiency is denoted by
.
The given data is as follows.
= 0.82,
= (21 + 273) K = 294 K
= 200 kPa,
= 1000 kPa
Therefore, calculate the final temperature as follows.
0.82 =
= 1633 K
Final temperature in degree celsius =
= 
Now, we will calculate the entropy as follows.

For 1 mole, 
It is known that for
the value of
= 0.028 kJ/mol.
Therefore, putting the given values into the above formula as follows.

= 
= 0.0346 kJ/mol
or, = 34.6 J/mol (as 1 kJ = 1000 J)
Therefore, entropy change of ammonia is 34.6 J/mol.
Answer:
The maximum wavelength of light for which a carbon-carbon triple bond could be broken by absorbing a single photon is 143 nm.
Explanation:
It takes 839 kJ/mol to break a carbon-carbon triple bond.
Energy required to break 1 mole of carbon-carbon triple bond = E = 839 kJ
E = 839 kJ/mol = 839,000 J/mol
Energy required to break 1 carbon-carbon triple bond = E'

The energy require to single carbon-carbon triple bond will corresponds to wavelength which is required to break the bond.
(Using planks equation)


The maximum wavelength of light for which a carbon-carbon triple bond could be broken by absorbing a single photon is 143 nm.
First, we determine the number of moles of barium phosphate. This is done using:
Moles = mass / Mr
Moles = 1 / 602
Moles = 0.002
Now, we see from the formula of the compound that each mole of barium phosphate has 2 moles of phosphorus (P). Therefore, the moles of phosphorus are:
0.002 * 2 = 0.004
The number of particles in one mole of substance is 6.02 x 10²³. The number of phosphorus atoms will be:
0.004 * 6.02 x 10²³
2.41 x 10²¹ atoms of phosphorus are present
Answer:
benzamide
Explanation:
Compound melting Point ,ºC Melting Pont Mixture, ºC
X 131 - 133
trans-cinnamic 133 - 134 110 - 120
acid
benzamide 128 - 130 130-132
malic acid 131 -133 114 -124
Benzoin 135 - 137 108 - 116
The compound X is benzamide since the melting point range is the one closest to this compound ( 130-132 ºC)
The reason there is not an exact match is not due due to the presence of impurities. The presence of impurities always lower the melting point ( it is a coligative property such as the melting point depresion of salt and water )
The reason for the deviation must be be some other factors such as preparation of the sample in the capillary, errors in reading the thermometer, rate of heating, etc.