LON-CAPA Assignment 1 PDF

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LON-CAPA ASSGINMENT 1 1. Use a calculator to evaluate the square root of 6.45×10-19. √{6.45 ×10−19 } = 8.03×10-10

2. Evaluate the following expression and express the answer in decimal or scientific notation rounded to the correct number of significant figures. 4.77 x 8.8 = 42

3. Evaluate the following expression and express the answer in scientific notation rounded to the correct number of significant figures. Also specify correct units. 586.8×10 -7 cm / 28.6×10 -2 s = 2.05×10-4 cm*s^-1

4. While driving in the U.S.A., a Canadian fuels their car at a cost of US$3.44 per gallon (US). Given that the monetary exchange rate is 0.755 US$/Can$, and the density of the fuel is 0.626 g/mL, what is the mass of Can$40.00-worth of this fuel? 2.08×101 kg

If the vehicle consumes the gasoline at a rate of 6.77 L/100 km, how many miles can it travel on the above amount of gasoline? 3.05×102 miles

5. From 1967 until 1999, Canadian 10¢ and 25¢ coins were made of pure nickel which has a density of 8.902 g/cm3. Suppose each dime weighed 2.14 g and each quarter weighed 5.35 g. A small collection of dimes and quarters were submerged in 10.00 mL of water in a graduated cylinder causing the water level to rise to the 13.85 mL mark. What was the combined monetary value (in Can$) of those coins? $ 1.60

6. What is the Molecular Mass of HClO4? 100.46 amu

What is the Molar Mass of HClO4? 100.46 g

What is the mass percentage of oxygen in HClO4? 63.71 %

7. Stanislao Cannizarro (1826-1910) applied Dalton's (1766-1844) Atomic Theory, Avogadro's (1776-1850) Hypothesis, and the experimental methods of Gay-Lussac (1778-1850), to correctly deduce relative atomic masses for various elements. For example, suppose a nameless element (X) was found to occur in three different substances (A, B and C). The relative molecular masses of A, B, and C were found to be 33.70, 79.40 and 252.20 respectively, compared to an assigned value of exactly 2.00 for H2. Subsequently, these

substances were subjected to elemental analysis and were found to contain 94.1%, 59.9% and 25.2% of X respectively by mass. What is the (likely) relative atomic mass of X, on this scale? 15.87

What would be the correct chemical symbol for X? O 8. Indicate whether each of the following statements is correct (Yes or No). The chemical formula must be correct and the name of the compound must correspond to it unambiguously, and in accordance with the naming conventions taught. No: SO3 is sulfur oxide. Yes: KClO3 is potassium chlorate. Yes: Ag2S is silver sulfide. Yes: Sn(NO3)4 is tin(IV) nitrate. Yes: HNO3 is nitric acid. 9. There are some very small variations in relative isotopic abundances in materials obtained from different natural sources. This is particularly evident in the relative abundances of the isotopes of the element boron. Boron from a particular geological sample is analyzed and found to contain: 10B (10.012937 amu), 19.798% (numerical abundance) and 11B (11.009350 amu), 80.202% (numerical abundance) Calculate the average atomic mass of boron obtained from this sample. 10.8121 amu

10. corresponding to the molecular masses labeled on the x-axis. The height of each bar gives the fraction of all molecules having the corresponding mass. Iodine has only a single, stable, naturally-occurring isotope (127I atomic mass 126.90447 amu). Fluorine has only a single, stable, naturally-occurring isotope (19F atomic mass 18.98840322 amu). There are exactly two stable naturally-occurring isotopes of element "X". What is the atomic mass of the more massive isotope of element X? 80.91629 amu

What is the atomic mass of the less massive isotope of element X? 78.91834 amu

What is the molar mass of the compound IX2F? 305.7 g/mol

11. A natural product has the molecular formula C18H25O4. What is the molar mass of this compound (in g/mol)? 305.4 g/mol

How many moles of C18H25O4 molecules are in 163 mg of this compound? 5.34×10-4

What is the mass of 0.150 mol of this compound? 45.8 g

How many oxygen atoms are in 2.05 pg of this compound? 1.62×1010

What is the mass of 3.44×1010 molecules of this compound? 1.74×10-11 g

12. Heme molecules are responsible for the red pigmentation of blood cells. Differing chemically isolated molecular heme compounds are named as "Heme X" (where "X" is a variable denoting the actual molecular fragments which are represented by the labels R3, R8, and R18). Suppose one molecule of Heme X contains 4 oxygen atoms, and Heme X is 9.82 % oxygen by weight. Using only this information and the atomic mass of oxygen, determine the molecular mass of Heme X. 652 amu

The Heme X molecule contains one chlorine atom. What mass of chlorine is found in 2.99 g of Heme X compound? 1.63×10-1 g

13. The class of ternary compounds called carboranes (containing the elements carbon, boron and hydrogen) have played a prominent role in many areas of fundamental chemical research. In particular, they have provided many interesting examples for testing theories on chemical bonding and structure. A particular carborane has the following mass percentages: 31.89%C and 10.71%H. What is the empirical formula of this compound? Choose appropriate coefficients in the formula below.

CB2H4...