Write the equation in standard form y x

cientists believe the population will grow by about 6.3% every year. Write an equation for the number of whales here every year after 2000

a in the form y = (x – h)2 + k.

titrated with a 0.200 M solution of the base, LiOH. Write the balanced chemical reaction for neutralization reaction: HClO4 (aq) + LiOH (aq) → LiClO4 (aq) + H2O (l) Write the NET ionic equation for the neutralization reaction. OH⁻ (aq) + H⁺ (aq) → H2O (l) Compute the pH of the titration solution. Show your work i) before any of the base is added ii) after 25. mL of base is added iii) after 50. mL of base is added A student performs the titration with the same chemicals but with smaller volumes of each chemical . Which of the following titration curves could represent the titration. Explain A because this entails a strong acid and a strong base. Question 2 A student performs a titration of an unknown acid with a strong base and gets the following titration curve: a) The student consults the list of pKa of acids shown below. If the acid is listed in the table below, which is the most likely identity of the unknown acid? Explain. Acid Ka HF 7.2 x 10-4 CH3COOH 1.8 x 10-5 H2CO3 4.3 x 10-7 HBrO 2.0 x 10-9 The unknown acid is HBrO because the calculated Ka is in between 50^-4 and 50^-6 and 2.0 x 10^-9 lies in between them. b) What is the initial molarity of the acid? 10^-3 = 0.001M Question 3 a) Describe the components and the composition of an effective buffer solution. Explain how the components of the buffer allow the buffer to maintain its pH. An effective buffer solution has a weak acid and its conjugate base or a weak base and its conjugate acid. A buffer solution is most effective when the ratio of its component concentrations is close to 1, also when the pH is equal to the pka of the acid.; The components of the buffer allow the buffer to maintain its pH because buffers can absorb excess H+ions or OH– ions. An employer is interviewing four applicants for a job as a laboratory technician and asks each how to prepare a buffer solution with a pH of 5.0. The following constants may be helpful: hydrazoic acid, pKa = 4.74 Boric acid, pKa = 9.23 Archita A. says she would mix equal molar solutions of hydrazoic (HN3) and sodium azide (NaN3) solutions. Bradley B. says she would mix equimolar Boric acid (H3BO3) and HCl solutions. Carlos C. says he would mix equimolar Boric Acid (H3BO3) and sodium dihydrogen borate (NaH2BO3) solutions. Delia D. says he would mix equimolar hydrazoic Acid (HN3) and NaOH solutions. b) Which of these applicants has given an appropriate procedure? Explain your answer Delia because she is using Sodium hydroxide which results in a pH of 5. NaOH is a strong base and in order to have an effective buffer a weak acid must be incorporated which is the HN3. c) Explain what is wrong with the erroneous procedures. The rest all incorporate a strong acid and a strong base or a weak acid and a weak base which don’ result in an effective buffer. d) The applicants have access to the 1 Liter volumes of each of the solutions listed above. They have access to graduated cylinders. In order to make 1.0 Liter of the correct 5.0 buffer solution, what volumes of the two chemicals must be mixed?

-2. Pick one. y=1\frac{1}{4}y=1 4 1 ​ y=-2x+\frac{3}{4}y=−2x+ 4 3 ​ y=\frac{3}{4}x-2y= 4 3 ​ x−2 y-\frac{3}{4}=-2\left(x+2\right)y− 4 3 ​ =−2(x+2)

Your answer should be written in slope-intercept form. P(0, 0), x = −4y − 18

action between an aqueous solution of Ammonium phosphate and the aqueous solution of Chromium (II) nitrate. Make sure to include physical states in all three equations.

mand is 18,200 rolls. When the demand increases to 26,200 rolls, the supply is 20,000 and the price is $1.24 per roll. Let x be the quantity in thousands of rolls. The table below gives the price-supply and price-demand equations. Price Equations for Toilet Paper Type Equation Price-Supply P = -0.04x + 2.04 Price-Demand P = 0.025x + 1.495 QUESTION 1 Find the supply at a price of $2 per roll. 1000 rolls 10,000 rolls 1 roll 5000 rolls QUESTION 2 Find the demand at a price of $2 per roll. 20.2 rolls 202 rolls 20,200 rolls 500 rolls QUESTION 3 Use the substitution method to find the equilibrium quantity. Round x to the nearest tenth first and then convert to thousands. Include the units in your answer. QUESTION 4 What is the equilibrium price? Write the answer in dollars and cents, rounding to the nearest cent.

elation) and write your analysis about the relationship between two variables in 2 or 3 sentences. Draw the line of best fit for your scatter plot Write the equation of line of best fit.

nd passes through the point (3,6).

units. Chemical Equation: Write a generic chemical equation for the dehydration of cobalt (II) chloride ∙ x hydrate (include the state symbols of the reactant and two products). [T2] Mass of Reactants and Products: a) Calculate the initial mass of the hydrated cobalt (II) chloride. [T1] b) Calculate the final mass of the anhydrous cobalt (II) chloride remaining in the cruiio8icible. [T1] c) Calculate the mass of water given off by the sample of hydrated cobalt (II) chloride. [T1] Moles of Products: a) Calculate the moles of anhydrous cobalt (II) chloride remaining in the crucible. [T1] b) Calculate the moles of water released from the hydrate. {T1] 4. Mole Ratio a) Create an experimental mole ratio between the b) and a). [T1] 5. Formula of Hydrate: State the chemical formula you have determined for this hydrate. Round the formula to the closest whole number value for x. [T1] Discussion/Conclusion Questions: [T6] Based on the chemical formula of the hydrate, calculate the percentage composition (percent by mass) of the hydrated cobalt (II) chloride. Remember to determine the percentage of each element (Co, Cl, H, and O). [T2] A possible source of systematic error in this experiment is insufficient heating. Suppose that the hydrate was not completely converted to the anhydrous form. Describe how this would affect: the calculated percent by mass of water and the experimental molecular formula (i.e. would x be higher, lower or the same). Suppose a student spilled some of the hydrated cobalt (II) chloride. Describe how this would affect the calculated percent by mass of water (would it be higher, lower or the same) and the experimental chemical formula of the hydrate. [T2]

d lead (II) sulfate precipitates (a) Write a balanced chemical equation for the reaction (b) Write the net ionic equation for the reaction (c) What type of reaction is occurring? (d) What is the limiting reagent? The excess reagent? (e) How many grams of lead (II) sulfate are formed? (f) In the lab, a chemistry student mixed the two solutions together and formed 9.40 g of lead (II) sulfate. What percent yield did the student obtain?

e form. (3.-5) (9.-13). I’ve found the slope I believe, it’s -4/3. I don’t know what to do now

ing points. Do not skip spaces! (2,5) (8,-7)

m high, 2 s into its flight. Write the equation relating the object’s height (y) to time (t), in the vertex form: ???? = ????(???? − ℎ)+2

m high, 2 s into its flight. Write the equation relating the object’s height (y) to time (t), in the vertex form: ???? = ????(???? − ℎ) 2 + �

e form f(x)=a(x-h)^2+k

chets and sells baby blankets, b. Each blanket requires 3 skeins of yarn, and the total number of skeins Facundo uses, y, varies directly as the number of blankets he crochets, b. Write an equation that models this relationship. 2. The weight of an object, w, varies inversely as the square of its distance from the center of Earth, d. When an astronaut stands in a training center on the surface of Earth (3,960 miles from the center), she weighs 155 pounds. To the nearest tenth of a pound, what will be the approximate weight of the astronaut when she is standing on a space station, in orbit 240 miles above the training center? 3. The square of g varies inversely as h. When g = 16, h = 2. What is the value of h when g = 40? 4. The number of days, d, it will take Manny to read a book varies inversely as the number of pages, p, he reads per day. If k is the constant of variation, which equation represents this situation? 5. The battery life for Bruhier’s cell phone is longer when he has fewer apps running. When only one app is running, the battery will last for 16 hours. When four apps are running, the battery will only last for 4 hours.

Use your result in (a) to solve the system: ■(x&+2y&+z&=1@x&y&+2z&=2@x&+y&+2z&=3) Question#2 (5) (modified from #13 p. 102 in your book) Solve the matrix equation for X X[■(1&1&1@1&2&0)]=[■(1&1&1@3&4&2)] Question#3 (5) (modified from #9 p. 102 in your book) Let [■(a&0&b&2@0&a&3&6@0&a&b&c+2)] be the augmented matrix of a linear system. Find for what values of a,b,c the system has: (i) a unique solution (ii) a one-parameter solution (iii) a two-parameter solution iv) no solution Question#4 (7) Write the matrix A=[■(-1&1&-1@1&1&-1@1&-1&2)] as a product of elementary matrices Question#5 (3) Find the determinant by any method: |■(0&-1&0&0&1@1&1&1&3&1@1&2&3&1&2@1&-1&0&3&1@1&-1&1&0&1)| Question#6 (3-2)Given thissystem: ■(x_1&+2x_2&+x_3&=1@x_1&-〖3x〗_2&+0x_3&=2@x_1&+0x_2&+2x_3&=3) a) Use Cramer’s method to solve for x_1 only b) Solve for the other variables by any method.

ation of the parabola in vertex form

By = C. (7,8), (6,-5)

s 75 inches. If the length is 20 inches, the width is 30 inches. Write an equation to relate the length and width of the box in this situation.

f $490 , and he is going to put in $70 per month. Maria opened her account with a starting amount of $670, and she is going to put in $40 per month. Let x be the number of months after today. (a)For each account, write an expression for the amount of money in the account after x months. (b)Write an equation to show that the two accounts have the same amount of money.

l unemployment rate dropped to about 4%. Find the average decline/year in unemployment rate from 2010 to 2018. Let x be the year since 2010 and y be the unemployment rate. Write an equation for unemployment rate versus year. Use your equation to estimate the unemployment rate in 2020.

Write a linear equation giving the median salary y in terms of the year X Then use the equation to predict the median salary.

r the graph in point-slope form. Explain your steps. 3. Write the equation for the graph in slope-intercept form. Explain your steps. 4. Which equation is the easiest to write by looking at the graph? Explain why your choice is easier than the other two equations.

r the graph in point-slope form. Explain your step 3. Write the equation for the graph in slope-intercept form. Explain your steps. 4. Which equation is the easiest to write by looking at the graph? Explain why your choice is easier than the other two equations.

or a circle with its center in the 4th quadrant and tangent to x=7, y =-4, and x=17.

The fees for the trip included a guide's fee as well as charge of $35 per person. The total cost for the group was $425. a) Write an equation in slope-intercept form to find the total cost C for p people. b) How much would it cost for