Answer:
1. The dye that absorbs at 530 nm.
Explanation:
The dye will absorb light to promote the transition of an electron from the HOMO to the LUMO orbital.
The higher the gap, the higher the energy of transition. The energy can be calculated by E = hc/λ, in which h and c are constants and λ is the wavelength.
The equation shows that the higher the energy, the higher the gap and the lower the wavelength.
Therefore, the dye with absorption at 530 nm has the higher HOMO-LUMO gap.
Answer:1.123 x 10^-31cm
Explanation:
mass of humming bird= 11.0g
speed= 1.20x10^2mph
but I mile = 1.6m
1km=1000
I mile = 1.6x10^3m
1.20x10^2mph= 1.6x10^3m /1mile x at 1.20 x 10^2
=1.932 x10^5m
recall that
1 hr= 60 min
1 min=60 secs, 1hr=3600s
Speed = distance/ time
=1.932 x10^5 / 3600= 5.366 x 10 ^1 m/s
m= a 11.0g= 11.0 x 10^-3kg
h=6.626*10^-34 (kg*m^2)/s
Wavelength = h/mu
= 6.626*10^-34/(11 x 10^-3 x 5.366x 10^1)
6.63x10^-34/ 590.26x 10 ^-3= 1.123 x10^-33m
but 1m = 100cm
1.123 x 10 ^-33 x 100 = 1.123 x 10^-31cm
de broglie wavelength of humming bird = 1.123 x 10 ^-31cm
The one that happens when the atoms of a substance are regrouped is : a new substance is formed.
After atoms being regrouped the molecules of the original substance will be different and the substance will have different properties from those of the reactans
Electronegativity of an element decreases as we move down a group on the periodic table and electronegativity increases while moving from left to right across a period on the periodic table.
Explanation:
- The electronegativity increases as we move from left to right across a period because from left to right across a period, the nuclear charge is increasing Hence the attraction for the valence electrons also increases.
- As we move down a group, the atoms of each element have an increasing number of energy levels. The distance between the nucleus and valence electron shell increases and reduces the attraction for valence electrons. Hence electronegativity decreases as we move from top to bottom down a group.