What is the mass number of a potassium (K) atom that has 20 neutrons? The mass number is __ Blank 1: square
__ is used as a decolorizing agent in the Anthony Method of capsule staining Copper sulfate Water 95% Alcohol 91% Isopropanol
What is the correct formula for calculating molar mass? Molar mass=Massdiv Moles Molar mass=Molesdiv Mass Molar mass=Volume+Density Molar mass=Molestimes Avogadro's number
Which of the following rules is applicable for balancing a chemical equation? Change only the coefficients Add the coefficients and change the subscripts Change only the subscripts Change the coefficients and the subscripts
A gas is cooled from 365 K to 285 K while its volume changes from 12.8 Lto 9.9 L The initial pressure of the gas is 1.9 atm. What is the final pressure of the gas rounded to the nearest tenth? 1.3 atm 2.9 atm 1.9 atm 9.9 atm
What happens to a material if it's dissolved in a solvent? The solute bonds to the solvent, forming new compounds. The solvent is split into its ions. The solute is split into its ions. The solute disappears forever.
The number of moles present in 180 grams of hydrochloric acid is approximately __ 4.75 5.00 4.25 4.50
How many oxygen molecules are needed to finish balancing the following equation? C_(4)H_(10)O+ldots O_(2)arrow 5H_(2)O+4CO_(2) 5 6 8 3 7
One mole of copper has a mass of 63.5 grams. Approximately how many atoms of copper are present in one mole of copper? 63 atoms 64 atoms 32times 10^23atoms 6times 10^23atoms
What is the total pressure in a 10.0 Lflask which contains 0.127 mol of H_(2)(g) and 0.288 mol of N_(2)(g) at 20.0^circ C 0.681 atm 0.306 atm 0.998 atm 0.693 atm
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
