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Some hydrogen gas a volume of 250cm3 at 20°c if the pressure is kept constant at what temperature will it's volume be 100cm3?
One chocolate chip used in making chocolate chip cookies has a mass of 0.269 g. How many chocolate chips are there in one mole of chocolate chips?
Carbon dioxide is an acidic oxide that reacts with aqueous calcium hydroxide.
Which type of reaction takes place?
Amylase was added to the test tube with starch solution, and placed in a thermostat at 37 ° C for 10 minutes. Then the contents of the tube were divided into two parts. Lugol's reagent was added to the first tube, and Fehling's reagent to the second after 10 minutes Lugol's reagent. What result can you get? Explain?
In a science laboratory, a group of scientists would like to test the reaction of argon and ethane (C2H6) vapor. A 2.00 L cylindrical container is filled with 3.50 g of argon at 60 ◦C. Ethane vapor is the added to the same container until the total pressure reached to 2.50 atm. Calculate the mass of ethane that was added in the container?
A solution is made by dissolving a 48.5 g of NaCl in 300.0 g acetic acid. What is the molal concentration of the solution
Carbon12 (C12) is stable and is the most abundant isotope of carbon. An ancient scrap of paper has 0.5 times the Carbon14 that a new piece of paper has. How many years old is the scrap of paper? (half-life of C14 is 5730 years)
The initial amount of the radioactive material B in a rock is determined to be 19.08 mg. Only 0.0038 g are left of B after 1,980 years. How much of the radioactive material B decayed? Express your final answer in four decimal places
how many atoms are in a sample of 4.000 moles of carbon
To obtain pure lead, lead (II) sulfide is burned in an atmosphere of pure oxygen. The products of the
reaction are lead and sulfur trioxide (SO3). Write a balanced chemical equation for this process. How many
grams of lead will be produced if 2.54 grams of PbS is burned with 1.88 g of O2? Express your answer to
the correct number of significant figures. Be sure to show all steps completed to arrive at the answer.
(Hint: be sure to work the problem with both PbS and O2)
