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| sec3.3 According to the SI definition, what is the amount of a substance that contains as many entities as there are in exactly 12g of carbon-12? | MOLE...This is the SI definition of a MOLE. |
| sec3.3 What is Avogadro's Number? | 6.022 x 10^23 |
| sec3.3 What is so important about Avogadro's Number? | Avogadro's Number is 6.022 x 10^23 , scientist use this number to define the number of units of a substance in one mole of a substance. That is, One mole of anything is 6.022 x 10^23 units of that substance. |
| sec3.3 An element's atomic mass in grams is equal to what? | The mass of one(1) mole of an element is equal to its atomic mass in grams |
| sec3.3 What number is exactly the number of atoms in exactly 12 grams of carbon-12 ? | Avogadro's Number , which is 6.022 x 10^23 |
| sec3.3 How many atoms are contained in exactly 12 grams of carbon-12 ? | There are 6.022 x 10^23 atoms of C-12 in 12 grams of carbon-12. Recall that 1 mole of anything equals 6.022 x 10^23 atoms/molecules of that substance. |
| sec3.3 What SI unit was established for use in counting atoms because samples of matter typically contain so many atoms? | The MOLE , abbreviated mol....The mole is the amount( or number) equal to the number of carbon atoms in exactly 12 grams of pure carbon-12. |
| sec3.3 One mole of something consists of how many units of that substance? | 6.022 x 10^23 units of a substance in one(1) mole of any substance. |
| sec3.3 A picture of just how great the value of a mole is, one may realize that one(1) mole of seconds represents a span of time ______?_______ as long as earth has already existed. | 4,000,000 times......That is, one mole of seconds is such a time lenght that it would exceed the current age of earth 4 million times. |
| sec3.3 A picture of just how great the value of a mole is, one may realize that one(1) mole of marbles is enough marbles to cover the entire earth to a depth of what? | 50 miles....One mole of marbles is such a great amount, that a mole of marbles would cover all of the earth to a deepness of 50 miles. |
| sec3.3 Assume you have oranges with an average mass of 0.5 pounds each and grapefruits with an average mass of 1.0 pounds each.Any two sacks for which the sack of grapefruit weighs TWICE as much as the sack of oranges will contain what ratio of grapefruits compared to oranges? | One(1) to One(1)....Since each grapefruit outweighs each orange by two times, it makes mathematical sense that doubling mass of the grapefruit present would give you the SAME NUMBER of grapefruit as you have oranges. |
| sec3.3 What SI UNIT is such that a sample of a natural element with a mass equal to the element's atomic mass expressed in grams contains one(1) mole of atoms? | MOLE |
| sec3.3 This metal is has a high Strenght-to-Mass Ratio and is also has a very high resistance to corrosion, often this metal is used for constructional purposes.What metal is most likely being described? | Aluminum ( Al ) |
| sec3.3 This is a metal that is an addition to steel in order to improve steel's resistance to corrosion.What metal is most likely being described? | Cobalt ( C0 ) |
| sec3.3 ( from TEACHER NOTES--not in text directly) A process where a sample of some material ( e.g. soil, waste or drinking water, bodily fluids,minerals,chemical compounds,etc.) is analyzed for its elemental and sometimes isotopic composition..This analysis can be qualitative ( simply determining what elements are present) or can be quantitative ( determining how much of each is present) or both.This type of analysis falls within the ambit of Analytical Chemistry.What is this process called? | Elemental Analysis, often abbreviated EA...For synthetic chemist, EA almost always refers to CHNX analysis. |
| s( from TEACHER NOTES--not in text directly) ec3.3 This chemistry field utilizes a set of instruments in order to decipher the chemical nature of our world. | Analytical Chemistry |
| sec3.3 ( from TEACHER NOTES--not in text directly) What is CHNX as per concering synthetic chemistry? | The determination of the percentage weights of carbon, hydrogen, nitrogen , and heteroatoms(X)(halogens,sulfur) of a sample, of which this information is vital for determination of the structure of an unknown compound as well as to help scientist ascertain (figure out) the structure and purity of a synthesized compound. |
| sec3.3( from TEACHER NOTES--not in text directly) This is the most common form of Elemental Analysis, accomplished by combustion analysis.What if this form of EA? | CHN analysis...CHN is the most common form of elemental analysis and it is accomplished by combustion analysis----a technique where a sample is burned in an excess of oxygen, and various traps collect the combustional products such as carbon dioxide,water, and nitric oxide.The weights of these combustional products then can be used to calculate the composition of the unknown sample. |
| sec3.3( from TEACHER NOTES--not in text directly) Another quantitative method used in elemental analysis(EA) is one that a sample is dissolved and then the element of interest is precipitated and its mass measured OR the element of interest is VOLATILIZED and the MASS LOST is measured.What method of EA is being described? | Gravimetry |
| sec3.3 ( from TEACHER NOTES--not in text directly) This is an Elemental Analysis method that is commonly used in both organic chemistry and analytical chemistry to determine the elemental composition ( a more precise empiricl formula) of a pure organic compound by combusting the sample under conditions where the resulting combustional products can be quantitatively analyzed...Once the number of moles of each combustional product is determined the empirical formula or a partial formula of the original compound can be calculated.What is being described? | Combustion Analysis (aka combustional analysis) |
