Which of the following processes produces a decrease in the entropy of the system? D dissolution of solid KCI in water D melting ice to form water D boiling water to form steam mixing of two gases into one container D freezing water to form ice
Only about 25% of useful energy is produced in combustion (cars) True False
Question 2 Describe the difference between molecular and ionic compounds. square
Which of the following are the reactants of the chemical equation 2H_(2)+O_(2)... 2H_(2)O O_(2) C_(3)H_(13) H
Hexane, C_(6)H_(14) would have which of the following fragments in its mass spectrum? Check all that apply. (m)/(z)=32 (m)/(z)=57 (m)/(z)=29 (m)/(z)=43
Which neutral atom has the following electron configuration: 1s^22s^22p^63s^23p^64s^23d^104p^65s^24d^105p^66s^2 Enter the chemical symbol for the element. View Available Hint(s)
Calculate the density in grams per liter of HF at STP. Be sure your answer has the correct number of significant figures. Note: For molar mass calculations, round to the hundredths place. square (g)/(L)
Which of the following indicators will be used in this experiment to detect the stoichiometric point? KHP Hygroscopic Phenolphthalein Methyl blue Potassium hydrogen phthlate
How many hours would it take to reduce one mole of Al^+3 to aluminum using a current of 22.2 Amps? A) 13020 hours B) 3.6 hours C) 0.22 hours D) 217 hours
Question 20 of 25 What is a network solid? A. A crystalline solid held together by intermolecular forces B. A crystalline solid held together by metallic bonds C. A crystalline solid held together by covalent bonds D. A crystalline solid held together by charge attractions
Phosphorus reacts with iodine as shown in the chemical reaction below.What is the percent yield of the reaction if 28.2 g $Pl_{3}$ is obtained from the reaction of 48.0 g of 12 with excess phosphorus? $2P(s)+3I_{2}(s)\rightarrow 2PI_{3}(s)$ 51.7 g 51.48 51.5 g None of the above 51.98
Select the pair that has the larger atom or ion listed first. $Br^{-},Se^{2-}$ $S,S^{2-}$ $Cl,Cl^{-}$ $F^{-},Ne$ $P,P^{3-}$
What information do you need to look at on the SDS? There is 1 correct answer. Look at Section 2 - Hazards Look at Section 3 Composition / Information on Ingredients Look at Section 4 - First Aid Measures Look at Section 5 - Fire-Fighting Measures Look at Section 6 - Accidental Release Measures
Breaking bonds is hydrolysis. is dehydration synthesis. stores energy. is endergonic.
Which statements are true regarding reaction rates'[Select all that apply.] Larger activation energies are associated with faster reaction rates. Higher reactant concentrations are associated with faster reaction rates. Reducing the activation energy for a reaction increases its reaction rate. Reaction rates depend on how likely molecules are to collide in the correct orientation to react. Reactions that give off heat occur rapidly. Reactions that absorb heat occur rapidly. Large changes in enthalpy are associated with fast reaction rates. At high temperatures molecules are more likely to collide with enough energy to initiate a reaction. Two molecules must collide with one another to react.
If 5.00 g of gray iron powder reacts with 2.38 g of red phosphorus powder, what is the mass of the iron phosphide product? $\square $
How many oxygen molecules do we need to produce four molecules of water? a) 4 b) 2 C) 3 d) 1
6. How many hydrogen atoms are in the chemical formula $C_{6}H_{12}O_{6}$ o 6 24 18 12
What type of chemical reaction is illustrated in the following example? $FeBr_{3}(aq)+AgNO_{3}(aq)\rightarrow Fe(NO_{3})_{3}(aq)+AgBr(s)$ combination reaction decomposition reaction single-replacement reaction double-replacement reaction neutralization reaction
Foamers and defoamers work by affecting the __ of liquid/gas separation. Fill in the blank.
