CHM 134 General Biochemistry I

Test 3, Fall season 2009 – Drs. Foy and Steel

Name

SOLUTIONS

1 . ( 2 points) Calculate the amount of moles in 0. forty one g ti..

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2 . ( 2 points) What is the mass of 5. 1 mol S?

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3. ( 2 points) A three or more. 6 g sample of lithium consists of how a large number of atoms?.

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some. (4 points) The thickness of iron is six. 87 g/cm3. Calculate the quantity of iron atoms present in a cube that has an edge of 3. 00 cm.

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5. (4 points) You have 0. 330 mole of every of the subsequent elements: End up being, B, Bayerischer rundfunk, Ba, and Bi. Which in turn sample provides the largest mass and so why?

Since all these samples have the same number of atoms (based on the moles) the sample while using heaviest atoms will have the greatest mass. Therefore, the bismuth (Bi) sample will have the greatest mass because its atoms have the very best atomic mass, about 209 g/mol.

6th. (4 points) Calculate the molar mass of Magnesium in grams/mol given the subsequent data (Show your complete calculation):

Isotope

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natural

plethora

isotope mass

(grams/mol)

24

78. 00%

23. 9858

25

twelve. 00%

24. 9858

twenty six

11. 01%

25. 9826

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Mg

Magnesium

Mg

several. (4 points) If an typical grain of rice includes a volume corresponding to 6. 0mm3, what is the volume of 2. 5 moles of rice reported in cu inches?

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8. (3 points) What mass of He contains the same number of atoms as five. 00 g Kr?.

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on the lookout for. (15 points) Complete the table of names and formulas.

Method

Name

Fe2(Cr2O7)3

iron (III) dichromate

NaCH3COO

Sodium acetate

SiCl4

silicon tetrachloride

Pb(OH)4

lead (IV) hydroxide

KClO3

potassium chlorate

GaPO4

gallium phosphate

KClO4

potassium perchlorate

CH3COOH

lactic acid

N2O5

dinitrogen pentaoxide

Al(CN)3

aluminum cyanide

Ca(NO3)2

calcium nitrate

SF6

sulfur hexafluoride

CrO

chrominum (II) oxide

RbCl

rubidium chloride

P4 S9...