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1. What is biological opportunism and give one example?
2. A bacteriophage has A-form DNA. A deletion mutant has a length of 10.4 μm instead of 15 μm. How many base pairs are missing from this mutant?
3. Explain how G-quadruplex binding molecules could be developed into potential anticancer drugs.
4. What are the percentage of all the bases (A, C, & G) in DNA that is 20% thymine?
5. The base sequence of one of the strands of a 20-bp duplex DNA is 5'-TCCGTTCGACGGTACATC-3' write the base sequence of its complementary strand.
- You are reacting an excess amount of hydrochloric acid with 150.0mL of sodium carbonate solution.
4.1L of carbon dioxide gas was collected at STP. Reaction yield was 85%.
What was the concentration of sodium carbonate solution used in this reaction?
- 200.0mL of hydrochloric acid solution reacted with 200.0 mL of sodium carbonate solution used as an excess reactant.
227.0mL of carbon dioxide gas was collected at 22.0OC temperature and 1.00 Atm pressure. Yield was 85%
Na2CO3(aq) + 2HCl(aq) 🡪 2NaCl(aq) + H2O(l) + CO2(g)
What was the concentration of hydrochloric acid?
In an experiment regarding composition analysis, an unknown is first fully combusted and then the products are analyzed. Combustion of 1.38 g of the unknown sample which contains C, H, O and N yields 1.72 g of CO2 and 1.18 g of H2O. In a separate test, another sample of the unknown with a mass of 22.34 g is found to contain 6.75 g of O.
Calculate the mass of oxygen, O from the 1.38 g sample?
- Propane and oxygen react according to the following equation.
C3H8(g) + 5O2(g) 🡪 3CO2(g) + 4H2O(g)
Calculate the volume of carbon dioxide and water vapour produced and the volume of oxygen remaining, when 20.0 L of propane reacts with 120.0 L of oxygen at STP.
- What volume of carbon dioxide will be produced in the reaction of 100.0mL of 1.1M sodium carbonate with 250.0mL 1.15M hydrochloric acid if its yield is 65%?
Na2CO3(aq) + 2HCl(aq) 🡪 2NaCl(aq) + H2O(l) + CO2(g)
A vessel containing an unknown volume of air in cm3 at 300•F and 101kilopascal was inverted and placed in cold ethanol. As the gas contracted the pressure was quadrupled while the temperature was reduced by onethird. What is the final volume of the gas in dm3
for the reaction between sodium carbonate and calcium hydroxide to form a precipitate. Write the net ionic equation of the reaction
galium has 2 naturally occuring isotopes with mass number 69 and 71 reapectively what is the percentage abundance of both isotopes if their relative atomic mass equals to 70.59atomic mass unit
Calculate the mass of water produced when 9.38 g
g of butane reacts with excess oxygen.
A student was asked to calculate the mass of ammonia, , in a solution given that there are 54 molecules present. The student’s calculation is shown below. Find the error(s) in the conversion factors, explain what the student did wrong and then correct the calculation. (note: there are 6.02x10²³ molecules per mole)
