When referring to mass sum of the atomic masses of the atoms represented by the formula of a molecular substance, the correct term used is A. atomic mass B. formula weight C. molecular mass D. molecular weight 12. A mole of CO2 contians A. 6.02 x 1023 ions C. 6.02 x 1023 formula ions B. 6.02 x 1023 molecules D. 6.02 x 1023 atoms 13. The mass of the products in a chemical reaction depends on the amount of A. excess reactant B. limiting reactant C. oxidizing agent D. reducing subtannce 14.
Identify the condensed formula of the following structure: A) (CH3)2CHCHClCH(CH3)2 B) CH3CH(CH3)CHClCH(CH3)2 Ans: C C) D) (CH3)2CHCHClC(CH3)3 (CH3)3CCHClCH(CH3)3 9. What is the chemical formula of the following carbon skeleton diagram? A) C8H14 Ans: C B) C8H16 C) C8H18 D) C8H20 10. How many hydrogen atoms are there on carbon atoms 1 and 2, respectively, in the structure below? A) 4, 1 B) 4, 0 Ans: D C) 3, 1 D) 3, 0 11.
chemistry 1a. Urea [(NH2)2CO] is produced by reacting ammonia with carbon dioxide with the release of water. In one process 637.2g of ammonia is treated with 1142g of carbon dioxide A. Write a balance equation for the above reaction B. Which of the 2 reactants is the limiting reagent C. Calculate the mass of urea formed D. How much excess reagent is left at the end of the reaction E. If the actual yield of urea formed was 980g what is its yield % a. Ans.
8.1 5) Based on the octet rule, iodine most likely forms an __________ ion. A) [pic] B) [pic] C) [pic] D) [pic] E) [pic] Answer: E Diff: 1 Page Ref: Sec. 8.1 6) There are __________ unpaired electrons in the Lewis symbol for an oxygen atom. A) 0 B) 1 C) 2 D) 4 E) 3 Answer: C Diff: 1 Page Ref: Sec. 8.1 7) How many unpaired electrons are there in the Lewis structures of a [pic] ion?
Atom Arrangement (shape) of the electron pairs around the atom Hybridisation of the atom Geometry around the atom N-1 Trigonal planar sp2 Angular/bent/V-shaped N-2 Tetrahedron sp3 Trigonal pyramidal C-3 Trigonal planar sp2 Trigonal planar C-4 Tetrahedron sp3 Tetrahedron The pKa of (the conjugate acid form at) N-1 is 3.12 and the pKa of (the conjugate acid form at) N-2 is 8.02. Draw the structure of the predominant form of nicotine that exists in the human body at pH 7.4. The pH is on the base side of 3.12 and so the conjugate base will predominate and the
k. What is the hydroxide concentration of a substance with a pOH of 8.5? 5. Write the dissociation equation for each of the following: l. sodium sulfate m. magnesium hydroxide n. calcium bromide. 6. Draw the Lewis structure for CH3Cl.
If 63% of the mass of pyrolusite is due to manganese, what is the empirical formula of pyrolusite? • MnO • Mn2O • Mn2O2 • MnO2 4. A compound with an empirical formula of C2H4Br has a molar mass of 215.90 g/mol. What is the molecular formula? • C4H8Br2 • C2H4Br • CHBr • C6H12Br3 5.
From these equilibrium concentrations, the equilibrium constant for the reaction can be determined. The purpose of this experiment is to determine the equilibrium constant for the following hydrolysis of an ester reaction: CH3COOCH2CH3 (aq) + H2O (l) CH3CH2OH (aq) + CH3COOH (aq) Ethyl Acetate Water Ethanol Acetic Acid (EtAc) (EtOH) (HAc) The equilibrium constant, Kc, for the reaction will have the following expression: Several reaction mixtures will be prepared with different initial amounts of ethyl
Find the concentration of the barium hydroxide in both mol.dm-3 and g.dm-3. [3] Ba(OH)2 + H2SO4 ( BaSO4 + 2H2O 7) In a titration, 25.0 cm3 of
September.22nd, 2013 Laboratory #5 Covalent Bonding-Molecular Models 1.A)Which of the electrons in a atom are used when predicting how the atom will bond with another atom? B)How is the periodic table used to determine the number or these electrons? Answer: A)The eletrons that are used when predicting how another atom will bond with another atom involves the outter valance of electrons. B)Atoms must have equal numbers of protons and electrons.The atomic number is the number located in the upper left corner. 2.Which combinations of elements in the periodic table are most likely to form covalent bonds/covalent compounds.