Answer:In a chemistry experiment, 10g of urea, NH2CONH2 (s), is dissolved in 150 mL of water in a simple calorimeter. A temperature decrease of 3.7oC is measured. Calculate the molar enthalpy of solution (∆Hs). ... an ideal gas B if 0.622 g sample of gas B occupies a volume of 300 mL at 35 °C and 1.038 atm.
Explanation:
18 g of silicon-32 will be present in 800 years.
A radioactive half-life refers to the amount of time it takes for half of the original isotope to decay and it's given by

where,
quantity of the substance remaining
the initial quantity of the substance
time elapsed
the half-life of the substance
From the given information we know:
The initial quantity of silicon-32 is 40 g.
The time elapsed is 800 years.
The half-life of silicone-32 is 710 years.
So, using the calculation above, we can determine how much silicon-32 is left.

Therefore,18 g of silicon-32 will be present in 800 years.
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A dichotomous key is an important scientific tool, used to identify different organisms, based the organism's observable traits. Dichotomous keys consist of a series of statements with two choices in each step that will lead users to the correct identification.
The answer is
d. To what temperature can the steam at 80 bar be cooled before a liquid will appear?
Answer: Last week, he accidentally dropped his coffee mug, which then fell on the floor due to gravity.
A scientific law can be defined as a law which followed universally. As a scientific law gives evidences and facts related to a natural phenomena. It is useful in scientific education and research.
Last week, he accidentally dropped his coffee mug, which then fell on the floor due to gravity is an example of law of gravity. The law of gravity states that objects are attracted to each other due to the magnitude of force acting between these objects. The earth exerts it's own gravitational force, to attract the objects towards itself.