1. 10mg KHCO3 is dissolved in enough water to make 20 ml of solution. calculate the molarity of the solution. Molar massaes: K = 39g/mol, H = 1g/mol, C = 12g/mol, O = 16g/mol
A. 5M B. 0.005M C. 2M D. 50mM E. 0.005mM
2. What is the hydroxide ion concentration of a water solution in which the hydronium ion concentration is 0.02M? Is the solution acidic or basic?
A. 2 x 10-12M , acidic (10의 -12승입니다) B. 2 x 10-2M , basic C. 2 x 10-2M , acidic D. 5 x 10-13M , basic E. 5 x 10-13M , acidic
3. In which of the following species does N have the lowest oxidation number?
A. N2 B. NO2 C. NO D. NH3 E. HNO3
4. Which of the following solutions has the highest osmotic pressure?
A. 0.15M Cr(NO3)3 B. 0.15M CaCl2 C. 0.15M KCl D. 0.15M Glucose E. All are the same since the concentrations are the same.
5. In polynucleotides, the nucleotide units are connected by which of the following bonds?
A. Phosphoanhydride B. Phosphoric acid C. Phosphoester D. Phosphoether E. Phosphodiester
6. Which substance could be decomposed by chemical reactions? (choose 2 answers)
A. water B. sugar C. mercury D. argon
7. Which main energy shell can accommodate a maximum number of 8 electrons?
A. 1 B. 2 C. 3 D. all of them
8. Magnesium forms an ion with a charge of
A. 1+ by loosing one electron B. 1- by gaining one electron C. 2+ by loosing two electrons D. 2- by gaining two electrons
9. Which solution contains the largest amount of glucose?
A. 0.5 L 2M solution B. 50mL 0.2M solution C. 1000mL 1M solution D. 0.25L 5M solution
10. choose the solution with the highest hydronium ion concentration
A. pH = 2HCI solution B. pH = 2 acetic acid solution C. 0.1 M HCI solution D. 0.1 M acetic acid solution
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