Answer: C
Explanation:
Sunlight
6 CO2 + 6 H2O --------------> C6H12O6 + 6 O2
Chlorophyll
Carbon(IV)oxide Water Glucose Oxygen
The Ancient Egyptians used simple sundials and divided days into smaller parts, and it has been suggested that as early as 1,500BC, they divided the interval between sunrise and sunset into 12 parts. ... Known as a clepsydra, it uses a flow of water to measure time.
Answer: 173 g ( 0.17 kg in right accuracy)
Explanation: Amount in moles is n = N/Na = 2.0·10^24 / 6.022·10^23 (1/mol).
n = 3.32116 mol. M(Cr) = 52.00 g/mol and mass m = nM = 172.7 g
Answer:
3. 3.45×10¯¹⁸ J.
4. 1.25×10¹⁵ Hz.
Explanation:
3. Determination of the energy of the photon.
Frequency (v) = 5.2×10¹⁵ Hz
Planck's constant (h) = 6.626×10¯³⁴ Js
Energy (E) =?
The energy of the photon can be obtained by using the following formula:
E = hv
E = 6.626×10¯³⁴ × 5.2×10¹⁵
E = 3.45×10¯¹⁸ J
Thus, the energy of the photon is 3.45×10¯¹⁸ J
4. Determination of the frequency of the radiation.
Wavelength (λ) = 2.4×10¯⁵ cm
Velocity (c) = 3×10⁸ m/s
Frequency (v) =?
Next, we shall convert 2.4×10¯⁵ cm to metre (m). This can be obtained as follow:
100 cm = 1 m
Therefore,
2.4×10¯⁵ cm = 2.4×10¯⁵ cm × 1 m /100 cm
2.4×10¯⁵ cm = 2.4×10¯⁷ m
Thus, 2.4×10¯⁵ cm is equivalent to 2.4×10¯⁷ m
Finally, we shall determine the frequency of the radiation by using the following formula as illustrated below:
Wavelength (λ) = 2.4×10¯⁷ m
Velocity (c) = 3×10⁸ m/s
Frequency (v) =?
v = c / λ
v = 3×10⁸ / 2.4×10¯⁷
v = 1.25×10¹⁵ Hz
Thus, the frequency of the radiation is 1.25×10¹⁵ Hz.
Answer : The formula for each of the following is:
(a) 
(b) 
(c) 
Explanation :
- Alkanes are hydrocarbon in which the carbon atoms are connected with single covalent bonds.
The general formula of alkanes is 
where n is the number of the carbon atoms present in a molecule of alkane.
- Alkenes are hydrocarbon in which the carbon atoms are connected with double covalent bonds.
The general formula of alkenes is 
where n is the number of the carbon atoms present in a molecule of alkene.
- Alkynes are hydrocarbon in which the carbon atoms are connected with triple covalent bonds.
The general formula of alkynes is 
where n is the number of the carbon atoms present in a molecule of alkyne.
(a) An alkane with 22 carbon atoms
Putting n = 22 in the general formula of alkane, we get the formula of alkane as, 
or
(b) An alkene with 17 carbon atoms
Putting n = 17 in the general formula of alkene, we get the formula of alkene as, 
or
(c) An alkyne with 13 carbon atoms
Putting n = 13 in the general formula of alkyne, we get the formula of alkyne as, 
or
