Methane is a tetrahedral molecule where each C-H is kept as far away from the others as possible due to electron-electron repulsion, resulting in a bond angle of 109.5˚ (Technically 109˚ 28' but I would just use the decimal version if I were you).
Hope this helps!
The chemical reaction for this is:
2 C2H6 + 7 O2 => 4 CO2 + 6 H2O
Solving for CO2 with each reactant will give:
21.0 g C2H6 x (1 mol C2H6/30.08 g C2H6) x (6 mol H2O/2
mol C2H6) x (18 g H2O/1 mol H2O) = 37.70 g H2O
110 g O2 x (1 mol O2/32.00 g O2) x (6 mol CO2/7 mol O2) x
(18 g H2O/1 mol H2O) = 53.04 g H2O
Since the amount of H2O in C2H6 is lower therefore C2H6
is the limiting reactant and the maximum amount of water is only 38 g H2O (2 significant digits)
ANswer:
38 g water
Answer: a) 
b) 
Explanation: Visible light is a form of electromagnetic wave.
Wavelength is defined as the distance between two successive crests of a wave. It is represented as symbol
.
Frequency is defined as the number of complete cycles happening per second. It is represented by the symbol
.
Wavelength and Frequency follow inverse relation,

where, c = speed of light = 
Wavelength and frequency of a wave is usually expressed in a range.
a) 
b) 