__ occurs when calcium and phosphate dissolve from hydroxyapatite crystals in the enamel. Select one: a. Decay b. Demineralization c. Remineralization d. Calcium depletion

Select all that apply Which of the following are examples of ways that fluid imbalances with changes in osmolarity can occur? Profuse sweating Volume depletion Volume excess Water intoxication

A 55.3 g sample of brass is put into a calorimeter (see sketch at right) that contains 100.0 g of water. The brass sample starts off at $97.1^{\circ }C$ and the temperature of the water starts off at $17.0^{\circ }C$ When the temperature of the water stops changing it's $21.4^{\circ }C$ The pressure remains constant at 1 atm. Calculate the specific heat capacity of brass according to this experiment. Be sure your answer is rounded to the correct number of significant digits.

Which compound is capable of hydrogen bonding with itself in the liquid state? $CHCl_{3}$ $BeH_{2}$ $H_{2}CO$ $CH_{3}OH$ HCN

What is the percent of hydrogen in ammonium sulfate: $(NH_{4})_{2}SO_{4}$ $4.0\% $ $6.1\% $ $1.0\% $ $3.0\% $

What is equal in an equilibrium? a,the concentrations of reactant and products b.the rate constants for the forward and reverse reactions c.the time that a particular atom or molecule spends as a reactant and product d.the rate of the forward and reverse reaction

b Avogadro's number of C atoms or 0.870 mole Al atoms Avogadro's number of C atoms 0.870 mole Al atoms

Which statement is not a use for oxygen analysis? To prevent an improper mixture of gas and oxygen from forming in equipment. To determine how much of a particular substance is present in a process stream. To determine exactly how much excess air should be put into boilers and heaters for maximum efficiency and fuel economy. To prevent an explosive mixture from forming

The decomposition of $N_{2}O_{5}$ in solution in carbon tetrachloride proceeds via the reaction $2N_{2}O_{5}(soln)\rightarrow 4NO_{2}(soln)+O_{2}(soln)$ The reaction is first order and has a rate constant of $4.82\times 10^{-3}s^{-1}$ at $64^{\circ }C$ If the reaction is initiated with 0.072 mol in a 1.00-L vessel, how many moles remain after 151 s? 0.035 moles $1.6\times 10^{3}$ moles 0.067 moles 9.6 moles 0.074 moles

Which element has the incorrect expected charge? $N^{3-}$ $Ca^{2+}$ $Al^{3+}$ $Cl^{2-}$

23) The burning of coal produces sulfur dioxide, $SO_{2}$ a pollutant that slowly reacts in air to form $SO_{3}$ Sulfur trioxide dissolves into airborne water droplets to form a very corrosive solution of sulfuric acid. Which is a product of burning coal that hastens the transformation of sulfur dioxide into sulfur trioxide? A) Carbon dioxide B) Carbon monoxide C) Nitrogen dioxide D) Particles of ash D) Particles of ash C) Nitrogen dioxide B) Carbon monoxide A) Carbon dioxide