General Questions and Answers

12 Ammonia gas decomposes according to the equation 2NH3 g N g 3H g If 15 0 L of nitrogen is formed at STP how many liters of hydrogen will be produced al measured at STP 2 a 15 0 L b 30 0 L 15 x3 45 x2 90 von seol zsi ining 25 45 0 L 90 0 L 7 C d olled etil evit a bad boy bus sy nogie to noolled

dentify the substance that has the greatest solubility Baking soda Sand O Chalk Salt

3 Which of the following sets of products would be expected when strontium hydroxide is used to neutraliz hydrobromic acid x SrBr and H O b HOH and HBr bastio Hes and gol ad blow galwe d and notiplos a bad saqi metab SrBrOH and H BrOH SrBr and H O B

When 84 8 g of iron III oxide reacts with excess carbon monoxide iron is one of the products What is the theoretical yield of iron Round answers to 2 decim places Fe2O3 s 3 CO g 2 Fe s 3 CO g The theoretical yield of iron is type your answer g Fe

Violet has found a container of aluminum bromide that says it contains 0 71 moles of AlBr3 What is the mass of this sample of aluminum bromide Please round your answer to two digits after the decimal point and remember to include correct complete units including substance formula Your Answer

Rank the following from most reactive 1 to least reactive 5 Potassium Lithium Sodium Rubidium Argon Choose Choose Choose Choose Choose

During the fall Winds come in and give the storm a bit and summer thunderstorms of a rotation A form over the oceans tropical depresion is formed when the winds within the storm reach between 34 73 the storm is considered a tropical storm Once winds reach 74 mph and the mph storm has defined eye it is considered a hurricane Answer this question Is there a connection between climate change and hurricanes Using the picture above comes up with 3 pieces of evidence What specific data or observation supports your claim tha Then come up with 3 pieces of reasoning how does this piece of evidence support your claim What is the science principle that explains why nga links to the alain2

Match the descriptions to the words Reacts with metals Reacts with Nonmetals React to give away electrons React to gain electrons Increasing Electronegatvity causes greater reactivity Is reactive with 8 valence electrons Choose Choose Nonmetals Metals and Nonmetals Neither metals nor nonmetals Metals Choose Choose Choose

Given the equation below 28 02 grams of LiOH and excess CO2 what mass of H O can be produced Round your answer to two digits after the decimal point 2 LIOH CO Li CO3 H O Your Answer

1 point Calculate the percent yield if 22 63 g of silicon carbide are produced from a reaction between silicon dioxide and carbon represented by following equation reaction theoretically began with 50 00 g of silicon dioxide and should produce 31 22 g of silicon carbide Round answers to 2 decimal places SiO s 3 C s SIC s 2 CO g

Kristen dissolves 70 86 grams of NaOH in enough water to make 216 mL of solution What is the molarity of Kristen s solution Round your answer to two digits after the decimal point Your Answer

Three elements A Q and Z have the molar masses indicated in the table below Given a compound with a composition of 19 4 Q and 80 6 Z by mass what is the empirical formula of this compound Remember to enter subscripts as normal numbers ie H O is entered as H2O and to enter elements in the same order they were given element symbol A Q Z molar mass 15 45 g mol 20 05 g mol 41 62 g mol

urse Posttest Question 3 A microwave oven produces a heat of 900 J by utilizing 1200 J of electrical energy What is the efficiency of the microwave oven O90 50 75 Points 2 30

LEARNING GOAL Calculate the total mass of reactants and the total mass of products in a balanced chemical equation 9 1 Calculate the total mass of the reactants and the products for each of the following equations a 2SO g O g b 4P s 50 g 2SO3 g 2P O5 s

Be sure to answer all parts The Haber process is an important industrial reaction that converts N and H to ammonia NH3 agricultural fertilizer and starting material for the synthesis of nitrate fertilizers Write a balanced equation for the Haber process Do not include states of matter in your answer

Be sure to answer all parts Write the net ionic equation for the reaction between AgNO3 aq and Na SO4 aq Be sure to incluc states of matter in your answer

7 Be sure to answer all parts Name each ionic compound a Cu 0 b SnSe a select b select C select c SnI4 select select select

Be sure to answer all parts Balance the chemical equation Do not include states of matter to your equation Al H SO4 Al SO4 3 H 1

Be sure to answer all parts Balance each equation Remember to include states of matter Al O3 s HCl aq AlCl3 aq H O 1

5 Be sure to answer all parts Write the formula for the ionic compound formed from each pair of element a barium and iodine b beryllium and chlorine

Does the molecular art represent a chemical change or a physical change O This represents a chemical change O This represents a physical change

Chemical change Physical change a Dissolving calcium chloride in water b d Burning gasoline to power a car metal heat 7

under the constant pressure and temperature the reaction of 40 mL of Cl2 gas with 25 mL of CH4 gas via the equation will produce a total of 55 65 20 38 Cl2 g CH4 8 HCI g CH3Cl g 22 mL of products

Calculate the amount of glycine and HCI required to prepare 1 L of 0 1 M buffer of a pH 2 0 and b pH 3 0 given that the pKa value of glycine carboxyl group is 2 4

Be sure to answer all parts Locate each element in the periodic table and classify it as a metal nonmetal or metalloid a thallium select b helium select c samarium select d indium nelest

38 2 points The freezing point of water is greater than less than the same as Previous the melting point of water

Rank the following elements in order of increasing size phosphorous fluorine germanium neon ar chlorine select select select select select

Give the period and group number for each element a gold b germanium c boron d cc e xenon Give the group as a number only e g 4A should be given as 14 Element a Gold b Germanium c Boron d Cobalt e Xenon Period Group 1000

36 37 38 39 40 41 43 2 points As the surface tension of a liquid increases the vapor pressure of the liquid will remain the same decrease increase Previous

30 2 points The solubility of solids in water generally increases at higher pressures while the solubility of gases in water decreases at higher pressures True False Previous

33 2 points The volume of a gas depends on the size of the gas True False Previous molecules

40 2 points A balloon will float in air if the gas filling it is less dense heavier more dense lighter Previous than air

8 Enter your answer in the provided box How many electrons are present in a 3s orbital electrons

According to this information Block Z is most likely composed of W O Balsa O Ebony O Maple X Y Z Type of Wood Balsa Ebony Maple Poplar A Density g cm 0 12 1 22 0 67 0 42

5 Each of the following radioisotopes is used in medicine For each isotope give its 1 atomic number 2 mass number 3 number of protons 4 number of neutrons 133 a Xe 54 131 b I 53 c copper 64 Atomic number Mass number Number of protons Number of neutrons

26 2 points A molecule in which the central atom has nonbonding electrons will always be Ononpolar ionic O polar Previous

13 TILS Which of the following properties of a liquid decreases as the intermolecular forces in the liquid increase O O O O vapor pressure viscosity surface tension boiling point Previous

9 2 points What is the solvent in champagne O Alcohol Water Carbon dioxide Previous

8 7 2 points A normal glucose solution contains 5 00 w v of glucose C6H12O6 What is the molarity of the solution 0 278 1 39 0 139 0 0278

How many different elements are represented in the table below XXN Y O 1 02 3 of Protons of Neutrons of Electrons 7 8 8 7 8 8 7 88

9 assignments 44325 9 module item id 11254709 7 A gas at 35 C takes up 550 mL What is its volume if the temperature decreases to 14 C

20 2 points At STP 32 grams of oxygen gas would have the same volume as 39 9 grams of argon gas 44 grams of carbon monoxide gas 8 gram of helium gas 19 grams of fluorine gas

15 2 points To cook a 3 minute egg in Lake Tahoe will require less more the same amount of time as it would in Stockton

Would SiH Cl2 be more soluble in a polar or nonpolar solvent Nonpolar Polar Previous

Gas Laws 5 A sample of gas in a 5 7 L container has a pressure of 0 79 atm If the volume if reduced to 2 9 L what is the new pressure 61 If a smole of gas at 25er has a prescurs of 600 mmHg what is the mos

1 650 mmHg atm 7 2 atm torr 2 3 250 7 kPa atm Standard Temperature and Pressure

3 2 points At standard temperature and pressure four grams of helium gas occupy a volume of 22 4 L Under the same conditions what volume would 4 grams of hydrogen gas occupy 44 8 L 11 2 L 5 6 L 22 4 L

600 10 0 points Select the true statement for the following reaction N 3H 2NH 1 Each N atom is oxidized from 1 to 3 Each Hatom is reduced from 1 to 0 2 Each N atom is reduced from 0 to 3 Each Hatom is oxidized from 0 to 1 3 Each N atom is oxidized from 0 to 3 Each H atom is reduced from 0 to 1 4 Each N atom is reduced from 0 to 6 Each II atom is oxidized from 0 to 2 5 Each N atom is oxidized from 0 to 6 Each II atom is reduced from 0 to 2 6 Each N atom is oxidized from 0 to 3 Each Hatom is reduced from 0 to 1 7 Each N atom is reduced from 1 to 3 Each II atom is oxidized from 1 to 0 8 Each N atom is reduced from 0 to 3

016 10 0 points Using the set of smallest whole number coef ficients to balance the redox equation Cr s CIO aq Cr OH s CIO aq in basic solution the sum of all coefficients is 6 6

017 part 1 of 4 10 0 points The redox reaction H aq Cr O aq C H5OH aq Cr aq C H O aq H O l is used in acidic solution in the Breatha lyzer test to determine the level of alcohol in the blood Which elements are undergoing changes in the oxidation state 1 Cr and I only 2 None of these 3 Cr and C only 4 0 and I only 018 part 2 of 4 10 0 points What is the initial oxidation number for Cr 1 6 5 7 019 part 3 of 4 10 0 points What is the coefficient of e in its balanced oxidation half reaction 020 part 4 of 4 10 0 points SENKI