Lab 7 Group Report

A model for the compound cyclopropane is shown. ball & stick C Submit Answer Use the References to access important values if needed for this question. labels Write a balanced chemical equation that shows the formation of cyclopropane from the elements carbon (C) and hydrogen (H₂). (Use the smallest integer coefficients possible and do not include states.) + Retry Entire Group 9 more group attempts remaining Previous Next Save and

4) 2 2 NaHCO3 (s) ----> 2 C(s) +3 Na(s) + 02(g) 1 H2(g) +

9. Using the following reaction 2NaBr +CaF2 2NAF + CaBr2 If 6 moles of CaF2 were added, what mass of CaBr2 (GFM = 199.9g/mol) will be produced? (round to the tenths place) Number unit

1. An exothermic reaction is taking place in a test tube , what would you expect to feel when you touch the outside of the test tube ?

Calculate reduced molar mass [in g/mol] for two particles with masses 30.4 g/mol and 57.7 g/mol. Note that your answer is smaller than either particle mass, hence the name "reduced" mass. Type your answer...

1. Determine the moles of copper and oxygen in the copper oxide from the data 2. What is the empirical formula for the copper oxide salt determined in the data 3. Write a balanced chemical equation for the methane/copper oxide reaction   DATA: Mass of empty test tube = 57.6382g Mass of tube + copper oxide = 59.8449 Mass of copper oxide = 2.2067 Mass of tube + copper = 59.3970 Mass of copper = 1.7588 Mass of Oxygen lost = 0.4479

(Show all calculations where appropriate.) 1. A student measured a 6.790 g sample of a hydrated salt. After heating, the mass of anhydrous salt was found to be 4.501 g. Use these data to calculate: a) The mass of water in the hydrated salt. b) The percent by mass of water in the hydrated salt. 2. If you have covered the topic of "the mole" in class, answer this question. Hint: Re-read the example in the introduction. 4.64 g of Na,SO,*xH,O were heated to yield 2.84 g of Na,SO4. What is the value of x?

a. If 1.00 g of aluminum hydroxide reacts with 3.00 g of sulfuric acid, what is the mass of water produced?   b. Aluminum metal and manganese (IV) oxide react to produce aluminum oxide and manganese metal. What mass of manganese (IV) oxide reacts to produce 1.00 kg of manganese metal?   c. Recreational vehicles use propane for cooking and heating. The combustion of propane and oxygen produces carbon dioxide and water. What mass of water is produced from the combustion of 10.0 g of propane, C3H8? Al(OH)3(s)+H2SO4(l)→Al2(SO4)3(aq)+H2O(l)

1. A sample of 2 tsp of sugar (C12H22O11) weighs 9.00 g. a. Record each step needed to calculate the moles and atoms of all elements present in the sample. b. Then, calculate the moles and atoms of each element in the sample of sugar on a sheet of paper. Show all work to answer this question. Take a photo of your work and upload the image into Photo 2.

Please show your work.

6.00 g of a certain Compound X , known to be made of carbon, hydrogen and perhaps oxygen, and to have a molecular molar mass of  46. g/mol , is burned completely in excess oxygen, and the mass of the products carefully measured:   product mass carbon dioxide 11.48g water 7.05g Use this information to find the molecular formula of X .

Number 5

Convert each mass to moles. Express the answer inscientific notation.a. 1.25 × 1 0 3 g Zn b. 1.00 kg Fe

Show all calculations and steps: 9. Determine the amount (in moles) of 53.45 g of lithium carbonate. Show all work.

Multiple Choice: How many atoms of carbon-14 are in the average human body given the following four facts: 1. Carbon makes up 23% of the human body by weight. 2. The average human body has a mass of 150 kg. 3. There are approximately 83 moles in every kg of carbon. 4. One in every trillion atoms of carbon is carbon-14.  a. 1,89 X 10 (exponent 15) b. 1,72 X 10 (exponent 15) c. 1,89 X 10 (exponent 16) d. 1,72 X 10 (exponent 16)

CHM130LL Take Home Quiz Week 13: Stoichiometry Each correct answer scores the points shown in brackets. For full credit, show each step in your math setup, include measurement units, and use the significant figures convention. Balance the reaction equations as needed. All elements and compounds are fictional. Google is not your friend. Alternate Universe Periodic Table A. 5.00 g/mol D. 10.00 g/mol E. 15.00 g/mol 20.00 g/mol 25.00 g/mol M. 30.00 g/mol 35.00 g/mol R 1. Calculate the molar mass and the mass percentage of R (%R) in G2ER4. [o1] Molar Mass175 %R 22 2. Calculate the amount (in moles) of A2 produced by decomposing 0.750 moles of DA3. [o1] DA3 (g) – D2(g) + (8) ) 3. Calculate the molar concentration (molarity) of a solution prepared by dissolving a 2.75-g sample of GRA in enough water to make 250.mL of solution. [o1] mote

Based on the graph below calculate the ratio of moles of H2O to moles of anhydrous KAl(SO4)2. Show all work including units. Note: Report the ratio to the closest whole number.   Aluminum Cup (Empty) 2.50 Aluminum Cup + 2.0 grams of Alum 4.50 Aluminum Cup + Alum After 1st Heating 3.60 Aluminum Cup + Alum After 2nd Heating 3.60 Mass of Released H2O 1.10 Molar mass of H2O 18.016 Moles of Released H2O

CALCULATIONS: SHOW COMPLETE "SET-UPS" (and the rounding off) for all calculations on the bottom of this a separate sheet. Use the correct number of significant figures and correct units. page or on 1. Mass of PbCrO4 formed 2. Moles of PbCrO4 formed 3. Formula of Limiting Reagent 4. Moles of PbCrO4 predicted by calculation 5. % Difference in moles formed and predicted gnificant figures and correct units. B 44.1248 44.3198 44.2921 A 44.0432 44.3279 14.25979 th both reagents. Briefly, indicate the B

20. According to the law of conservation of mass: A. energy will be lost during every endothermic reaction B. mass and atoms will be conserved during a chemical reaction C. energy will be conserved using coefficients in stoichiometry D. both B & C E. none of these

Which of the following is incorrect?   A. Fluorine will always have an oxidation number of -1 in all its compounds B. Oxidation numbers are always integers C. In a neutral compound, the sum of the oxidation numbers of all the atoms must be equal to zero D. Halogens usually have an oxidation number of -1 when bonded with other elements, except when bonded with oxygen.   Which of the following is correct?   A. Oxidation numbers are always integers B. Alkaline earth metals have an oxidation number of +1 in their compounds C. The oxidation number of hydrogen is +1 when bonded with non-metals, -1 when bonded with metals D. Alkali metals have an oxidation number of +2 in their compounds.

The mass of the crucible is 28.45g. The mass of the cover is 10.28g. Mass of crucible cover and lithium is 28.94g. Mass of crucible, cover, and lithium oxide-39.18g.  The molar masses of Li and O are 6.941 g-mol-1 and 16 g-mol-1. A) calculate moles of lithium used. B) calculate the moles of oxygen in the product. C) Determine the empirical formula for the lithium oxide using the simplest molar ratio.