Chapter 15.13, Problem 31ATS

Analytical chemistry is a particular field within the broader spectrum of the chemical sciences, in which many times the focus of analytical experiments is to develop new methods to analyze compounds, either structurally or by determining concentrations of compounds. One of the processes analytical chemists use to determine the exact concentration of a working solution is called standardization. In your own words, describe the differences between a primary, secondary, and tertiary standard, and describe the underlying concept behind the standardization process. Why is it done?

3. Using this data, calculate a value for Kc for the reaction, A. 2.06 x 104 B. 4.84 x 10-3 C. 0.223 D. 4.49 E. 20.2 2 NO(g) + Cl₂(g) 2. NOCI(g) Kc = 3.20 x 10-³ 2 NO2(g) 2 NO(g) + O₂(g) Kc = 15.5 4. Using the data, NOCI(g) + 1/2O2(g) NO2(g) + ½ Cl₂(g) 3 A (g) + 4 B (g) A3B4 (g) calculate a value for Kc for the reaction, 3 A (g) + 4 B -A3B4 (g) 2 AB (g) + AB2 (g) (g) Kc = 25 Kc = 3.75 2 AB (g) + AB2 (g)

What is the balanced equation for the complete combustion of bu- CH tane, 4 10? Write out the complete balanced equation for the combustion reac- tion, predicting the correct products. Use the equation editor. I || Normal : A A + Enter your answer here ® BIUS X₂ X X² √x 20 I₂

A pheromone is a type of volatile compound produced by a variety of insect species for chemical communication. These molecules can be used to signal alarm, to attract a mate, or to indicate the presence of food. The presence of 1.00 x 10-8 g of a pheromone can be sensed by another insect within a radius of 0.500 miles. Calculate the density of this pheromone. (1609 m = 1 mile) %3D Calculate the density (g/L) of the pheromone in this cylindrical air space.

6. C) Hydrated barium chloride can be crystallised from solution Hydrated barium chioride has the formula BaCl O and a molar mass of 244 3gmal Determine the value of x in the formula of BaCh•xH,O. Show your working.

||| O CHEMICAL REACTIONS Balancing chemical equations with interfering coefficients Balance the chemical equation below using the smallest possible whole number stoichiometric coefficients. CH,CH, (g) + O,(g) → CO,(g) + H,O(g) X Ś

/document/d/1KWoB0hrXolu7UEKbq4f8LBMHfpjHBRVU3qUzVI7K80U/edit Sample Work Format Tools Extensions Help + nt will $ 4 Normal text R f5 A % T 5 Calibri 12 13. The chemical equation for the decomposition of potassium chlorate (KCIO3 ) is 2 KCIO,(s) → 2 KCl(s) + 3 0₂(g) The molar masses of the elements in this equation are: K: 39.1 g/mol, Cl: 35.4 g/mol, O: 16.0 g/mol 담 ㅁ (b) How many moles of KCI are formed? Pathway: g of KCIO3 → mol KCIO3 → mol KCI Y If 30.6 g of potassium chlorate (KCIO3) reacts.. (a) How many moles of potassium chlorate(KCIO3) are there? Pathway: g of KCIO3 → mol KCIO3 7 + &1 BI U A 3 c) How many grams of KCI are formed? Pathway: g of KCIO3 → mol KCIO3 → mol KCI →g of KCI 18 U fg 8 I no 6 f10 © □ □E - †= = = = insert 9 5 $12 P prt scr L 7 64°F Mostly sunny G 1

You work in a research organization that is looking for markers of various diseases that can be used as a diagnostic for the disease. It has been reported in the past that high levels of Cu are found in the sweat of people with cystic fibrosis. One of the research projects is focused on looking for high levels of Cu in samples that can be obtained non-invasively such as saliva, sweat, hair, nails, etc. The lab will analyze large samples for Cu. What instrument would you recommend purchasing to support this work, Atomic absorption spectrophotometer or an inductively coupled plasma atomic spectrophotometer? Explain the basis for your decision.

Consider the balanced reaction 8 A + 4 B 8C+ 8 D. If 1.592 moles of B (MW = 26.51) are consumed, how many grams of A (MW = 35.96) are also consumed? %3D Report your answer to three decimal places (ignore significant figures).