Ba2+ and Cu2+, and Sr2+ and Li+
Problem One
You will use both m * c * deltaT and H = m * heat of fusion.
Givens
m = 12.4 grams
c = 0.1291
t1 = 26oC
t2 = 1204
heat of fusion (H_f) = 63.5 J/grams.
Equation
H = m * c * deltaT + m * H_f
Solution
H = 12.4 * 0.1291 * (1063 - 26) + 12.4 * 63.5
H = 1660.1 + 787.4
H = 2447.5 or 2447.47 is the exact answer. I have to leave the rounding to you. I have no idea where to round it although I suspect 2450 would be right for 3 sig digs.
Problem Two
Formula and Givens
t1 = 14.5
t2 = 50.0
E = 5680
c = 4.186
m = ??
E = m c * deltaT
Solution
5680 = m * 4.186 * (50 - 14.5)
5680 = m * 4.186 * (35.5)
5680 = m * 148.603 * m
m = 5680 / 148.603
m = 38.22 grams That isn't very much. Be very sure you are working in joules. You'd leave that many grams in the kettle after drying it thoroughly.
m = 38.2 to 3 sig digs.
Solution: Sentence D is a scientific statement.
Scientific statement is a statement that defines the science behind any situation. There should be any experimental result or observation to state any scientific statement. Also, the statement should be accepted by considering other scientific aspects.
Here, statement A can not be a scientific statement as different aromas of cooked food are liked by different people. Any one can find aroma of cooked food in copper better than the ceramic pot.
Thus, the statement can be proved wrong easily.
Statement B can not be a scientific statement as people can find the taste of normal water (without ice cubes) better than the ice cold water.
Statement C is not a scientific statement as there is no science behind watching baseball or ice hockey, it depends on the liking of today's people.
Statement D is a scientific statement because this can be scientifically proved.
An air mass is a large volume of air in the atmosphere thats mostly uniform in temperature and moisture. Air masses can extend thousands of kilometers across the surface of the Earth, and can reach from ground level to the stratosphere/10 miles into the atmosphere. an air mass over northern Canada is a continental polar air mass and is cold and dry. One that forms over the Indian Ocean is called a maritime tropical air mass and is warm and humid.
