3. Find the mass percent of oxygen in ethanol, C_(2)H_(6)O
BaSO_(4) is used in diagnostic nuclear medicine techniques because it is highly insoluble. K_(sp)=1.5times 10^-9 25^circ C Calculate the molar solubility of the salt. What is the concentration of Ba2+ions in the saturated solution? [Ba^2+]=[?]times 10^[?]M
50. For which of the following cleaning issues are general purpose detergents effective? Dirt and grime on the walls Grease in the exhaust hood Baked on food on ovenware Mineral build-up on equipment
True or False: Isotope refers to the electrical charge of the electron. True False
When the following half reaction is balanced, how many electrons are present and are they on the reactants or products side of the equation? Ti^2+(aq)arrow TiO_(2)(s) Number of electrons: square Side of equation: square
Polar solutes are soluble in Multiple Choice most ionic solvents polar solvents nonpolar solvents More than one of these choices are correct. None of the choices are correct.
Calculate the pH of a 1.0times 10^-8 M aqueous solution of hydrochloric acid (HCl). Round your answer to 2 decimal places. square
58) Which substance below is an ionic solid? A) Cu(s) B) H_(2)O(s) C) MgO(s) D) C_(6)H_(12)O_(6)(s) E) none of the above
The radical is generated when chlorine radicals react with ozone. Calculate the maximum wavelength (in nanometers) required to break a Cl-Cl bond in Cl_(2) (the precursor to chlorine radicals)Round your answer to 3 significant digits. Note: Reference the Bond energies and Fundamental Constants tables for additional information. square nm
An industrial chemist studying bleaching and sterilizing prepares several hypochlorite buffers. Find the pH of 0.150 M HClO and 0.100 M NaCIO. Be sure your answer has the correct number of significant figures. Note: Reference the K_(a) of acids at 25^circ C table for additional information. pH=square
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
