How many valence electrons are in the acetate ion C_(2)H_(3)O_(2)^- square
What is the approximate pH at the equivalence point of a weak acid- strong base titration if 25 mL of aqueous HF requires ; 30.00 mL of 0.400 M NaOH? K_(a)HF=6.76times 10^-4 a. 1.74 b. 5.75 c. 8.25 d. 12.26
vphich pure substance can be classified as an element? H_(2) NO_(3) NaCl H_(2)SO_(4)
Question 3 of 10 What property is used to calculate the pH of a solution? A. The hydrogen ion concentration in ppm B. The hydrogen ion concentration in mg/dL C. The hydrogen ion concentration in mol/L D. The hydrogen ion concentration in mol/kg
Give the IUPAC name for the organic compound shown: CH_(3)-CH-CH-CH_(2)-COOH chloro-isopropyl alcohol 3-chloropentanoic acid 3-chloropentanone 2-chloropentanal
Question 18 of 20 What is the name for Mg_(3)N_(2) A. Magnesium nitride B. Magnesium dinitride C. Trimagnesium dinitride D. Dimagnesium trinitride
Calculate the predicted melting point for iron. Fe given the melting points of ruthenium, Ru, (2310^circ C) and osmium, Os. (3045^circ C) 2678^circ C 735^circ C 5355^circ C 1575^circ C 3780^circ C
Which of the following is a radioactive nonmetal? Ra At Po Rn none of the above
What is the maximum number of electrons in a 4d orbital? 1 5 10 2 none of the above
Which of the following is true of an electron orbit? An electron orbit is a fixed energy state. An electron orbit increases in size with greater energy. An electron orbit represents an energy level. An electron orbit may contain eight electrons. all of the above
22. When sugar is mixed with water equilibrium is reached when molecules of sugar stop moving the dissolved sugar molecules are evenly distributed throughout the
For which of the properties would aluminum have a greater value than gallium? 1. Atomic radius 2. Ionic radius 3. Electronegativity 4. Ionization energy
1A. Which of the following is most likely a significant cause of the general trend indicated by the graph? A. Reduction of ozone concentration in the upper atmosphere B. Reduction in size of polar ice caps C. Increase in energy output of the sun D. Increase in evaporation of ocean water E. Increase in consumption of fossil fuels 1B. Based on the results of the graph, which oceanic changes will be observed? A. pH will decrease, but the ocean will remain basic B. pH will increase and the ocean will become more basic C. pH will decrease and the ocean will become acidic D. pH will not significantly change 2A. When "strong," these dissociate completely in solution. A. Acid B. Base C. Both 2B. Is a proton-donor when dissolved in solution. A. Acid B. Base C. Both 2C. A solution with a pH greater than 7, up to 14. A. Acid B. Base C. Both 2D. A solution that contains more hydronium ions $(H3O+)$ than hydroxide ions $(OH-).$ A. Acid B. Base C. Both
Question 7 Match the definition with the correct term about the atom in relation to the periodic table. number of protons in the nucleus of an $\square $ atom [Choose] [Choose] total number of protons and neutrons in mass number the nucleus of an atom atomic mass atomic number $\square $ weighted, average mass of all isotopes of a naturally occurring element 1 pts
Properly identify the following ions (some answers will be used twice and some answers will not be used at all) magnesium $\square $ phosphate $\square $ ammonium $\square $ chloride $\square $ iron (III) $\square $ perchlorate $\square $
have gone into the field to take water samples from lakes in your town. note the following observations: Lake A contained many fish swimming in its waters. Lake B had very few fish swimming in its waters, and a few dead fish floating on the water. u return to your lab and take pH readings for each mple. Think about how acids and bases would affect the water quality in the two lakes. Which set of pH data would you expect to see based on your observations? Lake A: $pH=4.5$ Lake B: $pH=7.5$ Lake A: $pH=8.3$ Lake B: $pH=3.7$ Lake A: $pH=6.6$ Lake B: $pH=6.8$ Lake A: $pH=10.2$ Lake B: $pH=1.7$
A buffer consists of a weak acid and its conjugate hase in the same solution. Match the weak acid-conjugate base pairs that could be used to make a buffer. (Carvat does not show subscripts HCOOH $\square $ [Choose] $HC2H3O2$ $\square $ : HCN [Choose] H2O $NaCOOH$ $NaC2H3O2$ $NaOH$ $HCl$ $HaCN$ Question 9 aspts
${}_{2}^{4}He$ How many protons does He have? a b b C 2 d 6
Student B: At the beginning of the reaction the rate of the forward reaction was higher than the rate of the reverse reaction: ammonia and water were turning into ammonium hydroxide. But now, the rate of the reverse reaction is higher. Which student has the most accurate answer? Choose 1 answer: A Student A B Student B C Both students' answers are correct.
The number of atoms in a mole of something remains the same, but the mass of a mole depends on how many atoms you have the average atomic mass of the elements
