<span>ΔE = -RH [(1/nf2) - (1/ni2)]ΔE = -2.18 x10-18 J [(1/32) - (1/52)]ΔE = -1.55 x10-19 JE = hc/λλ = hc/Eλ = [(6.63 x10-34 J.s.) x (3.00 x1017 nm/s)] /(1.55 x10-19 J)λ = 1280nm</span>
Answer:
To determine the amount of heat the gold has absorbed to melt, we simply multiply the mass of the block of ice to the heat of fusion of water which is given above. We calculate as follows:
Heat = 20.0 g (35.4 g)
Heat = 1290 J
Answer:
D.) H-O
Explanation:
Polarity is determined based on the difference in electronegativity of the atoms. The greater the difference, the more polar the bond. The general trend is that the atoms in the top-right corner of the periodic table are the most electronegative.
A.) is incorrect because H-H has no electronegativity difference, making it nonpolar.
B.) and C.) are incorrect because their electronegativity differences are not the greatest.
D.) is correct because the electronegativity difference between the H and O is the greatest.
Answer:
Carbon dioxide levels in the Earth's atmosphere have been steadily increasing.
Carbon has a longer average lifetime in the atmosphere.
Explanation:
Today the level of carbon dioxide is higher than at any time in human history. Scientists widely agree that Earth’s average surface temperature has already increased by about 2 F (1 C) since the 1880s, and that human-caused increases in carbon dioxide and other heat-trapping gases are extremely likely to be responsible.
The lifetime in the air of CO2, the most significant man-made greenhouse gas, is probably the most difficult to determine, because there are several processes that remove carbon dioxide from the atmosphere. Between 65% and 80% of CO2 released into the air dissolves into the ocean over a period of 20–200 years.
Answer:
Always carry the microscope with two hands. One on the arm and one underneath the base of the microscope.
