Chemistry in our lives

The melting point of benzene is ${5.5}^{\circ }\mathrm{C}$ and its boiling point is ${80.1}^{\circ }\mathrm{C}$. Sketch a heating curve for benzene from $0^{o}C to {100}^{o}C$

a. What is the state of benzene at ${15}^{\circ }\mathrm{C}$?

b. What happens on the curve at $5.5^{o}C$?

c. What is the state of benzene at ${63}^{o}C$?

d. What is the state of benzene at ${98}^{o}C$?

e. At what temperature will both liquid and gas be present?

Identify each of the following as a physical or chemical property= (3.2)

a. Gold is shiny.

h. Gold melts at $1064{}^{\circ }\mathrm{C}$.

c. Gold is a good conductor of electricity.

d. When gold reacts with sulfur, a block sulfide compound forms.

Write one sentence definition for each of the following:

a. Chemistry

b. Chemicals

Ask two of your friends (not in this class) to define the terms in problem 1.1. Do their answers agree with the definition you provided?

Obtain a bottle of multivitamins and read the list of ingredients. What are the four chemicals from the list?

Obtain a box of breakfast cereal and read the list of ingredients. What are four chemicals from the list?

Read the labels of some items found in your medicine cabinet. What are the names of some chemicals contained in those items? 

Read the labels on products used to wash dishes. What are the names of some chemicals contained in those products?

Identify each activity, a to f, as an observation, a hypothesis, an experiment, or a conclusion. At a popular restaurant, where Chang is the head chef, the following occurred: 

a. Chang determined that  Customers rated the sesame sales of the house salad seed dressing as the best. had dropped. 

b. Chang decided that the house salad needed a new dressing. 

c. In a taste test, Chang prepared four bowls of lettuce, each with a new dressing: sesame seed, olive oil, balsamic vinegar, creamy Italian, and blue cheese. 

d. Tasters rated the sesame seed salad dressing as the favorite. 

e. After two weeks, Chang noted that the orders for the house salad with the new sesame seed dressing had doubled. 

f. Chang decided that the sesame seed dressing improved the sales of the house salad because the sesame seed dressing enhanced the taste.

Identify each activity, a to f, as an observation, a hypothesis, an experiment, or a conclusion. Lucia wants to develop a process for dyeing shirts so that the color will not fade when the shirt is washed. She proceeds with the following activities:

a. Lucia notices that the dye in a design fades when the shirt is washed. 

b. Lucia decides that the dye needs something to help it combine with the fabric.

c. She places a spot of dye on each of the four shirts and then places each one separately in water, saltwater, vinegar, and baking soda and water. d. After one hour, all the shirts are removed and washed with a detergent. 

e. Lucia notices that the dye has faded on the shirts in water,  saltwater, and baking soda, whereas the dye did not fade on the shirt soaked in vinegar. 

f. Lucia thinks that the vinegar binds with the dye so it does 

not fade when the shirt is washed.

Identify each of the following as an observation, a hypothesis,  an experiment, or a conclusion: 

a. One hour after drinking a glass of regular milk, Jim experienced stomach cramps.

b. Jim thinks he may be lactose intolerant. 

c. Jim drinks a glass of lactose-free milk and does not have any stomach cramps.

d. Jim drinks a glass of regular milk to which he has added lactase, an enzyme that breaks down lactose, and has no stomach cramps.

Identify each of the following as an observation, a hypothesis, an experiment, or a conclusion: 

a. Sally thinks she may be allergic to shrimp. 

b. Yesterday, one hour after Sally ate a shrimp salad, she broke out in hives. 

c. Today, Sally had some soup that contained shrimp, but she did not break out in hives. 

d. Sally realizes that she does not have an allergy to shrimp. 

What are four things you can do to help yourself to succeed in chemistry?

What are four things that would make it difficult for you to learn chemistry? 

A student in your class asks you for advice on learning chemistry. Which of the following might you suggest?

a. forming a study group 

b. skipping class 

c. asking yourself questions while reading the text 

d. waiting until the night before an exam to study 

e. answering the Engage questions 

A student in your class asks you for advice on learning chemistry. Which of the following might you suggest? 

a. studying different topics at the same time 

b. not reading the text; it's never on the test 

c. attending review sessions 

d. working on the problems again after a few days 

e. keeping a problem notebook.

What is the place value for the bold digit?

a. $7.32\mathbf{8}8$

b. $1\mathbf{6}.1234$

c. $4\mathbf{6}75.99$

What is the place value for the bold digit?

a. $97.\mathbf{5}689$

b. $3\mathbf{7}5.88$

c.  $46.1\mathbf{0}00$

Evaluate each of the following:

a. $15-\left(-8\right)=\_\_\_$

b. $-8+\left(-22\right)=\_\_\_\_$

c. $4\times \left(-2\right)+6=\_\_\_$

Evaluate each of the following:

a.  $-11-\left(-9\right)=\_\_\_$.

b. $34+\left(-55\right)=\_\_\_$.

c. $\frac{-56}{8}=\_\_\_$.

Solve each of the following for $a$ :

a. $4a+4=40$.

b. $\frac{a}{6}=7$.

Solve each of the following for $b$:

a. $2b+7=b+10$.

b. $3b-4=24-b$.

a. What does the title indicate about the graph?

b. What is measured on the vertical axis?

c. What is the range of values on the vertical axis?

d. Does the temperature increase or decrease with an increase in time?

a. What is measured on the horizontal axis?

b. What is the range of value on the horizontal axis?

c. What is the temperature of the tea after $20$ min?

d. How many minutes were needed to reach a temperature of $45°C$ ?

a. A clinic had $25$  patients on Friday morning. If $21$ patients were given flu shots, what percentage of the patients received flu shots? Express your answer to the one's place.

b. An alloy contains 56 g of pure silver and 22 g of pure copper. What is the percentage of silver in the alloy? Express your answer to the one's place.

c. A collection of coins contains $11$ nickels, $5$ quarters, and $7$dimes. What is the percentage of dimes in the collection? Express your answer to the one's place.

a. At a local hospital, $35$ babies were born. If $22$were boys, what percentage of the newborns were boys? Express your answer to the one's place.

b. An alloy contains $67 g$ pure gold and $35 g$ pure zinc. What is the percentage of zinc in the alloy? Express your answer to the one's place.

c. A collection of coins contains  $15$  pennies, $14$ dimes, and 6 quarters. What is the percentage of pennies in the collection? Express your answer to the one's place.

Write each of the following in scientific notation: 

a. $55000$

b. $480$

c. $0.000 005$

d. $0.000 14$

e. $0.0072$

f. $670 000$

 Write each of the following in scientific notation: 

a. $180 000 000$

b.  $0.000 06$

c. $750$

d. $0.15$

e. $0.024$

f. $1500$

Which number in each of the following pairs is larger? 

a. $7.2 \times {10}^3 or 8.2\times {10}^2$

b.  $4.5 \times {10 }^{-4} or 3.2 \times {10}^{-2}$

c.  $1 \times {10}^4 or 1 \times {10}^{-4}$

d. $0.000 52 or 6.8 \times {10}^{-2}$

Which number in each of the following pairs is smaller? 

a.  $4.9\times {10}^{-3} or 5.5\times {10}^{-9}$

b. $1250 or 3.4 \times {10}^2$

c.  $0.000 000 4 or 5.0\times {10}^2$

d.  $2.50 \times {10}^2 or 4 \times {10}^5$

A container was found in the home of the victim that contained $120 g$ of ethylene glycol in $450 g$ of liquid. What was the percentage of ethylene glycol? Express your answer to the ones place.

If the toxic quantity is $1.5 g$of ethylene glycol per $1000 g$ of body mass, what percentage of ethylene glycol is fatal?

A "chemical-free" shampoo includes the following ingredients: water, cocamide, glycerin, and citric acid. Is the shampoo truly "chemical-free"? $\left(1.1\right)$

A "chemical-free" sunscreen includes the following ingredients: titanium dioxide, vitamin, and vitamin. Is the sunscreen truly "chemical-free"? $\left(1.1\right)$

According to Sherlock Holmes, "One must follow the rules of scientific inquiry, gathering, observing, and testing data, then formulating, modifying, and rejecting hypotheses, until only one remain." Did Holmes use the scientific method? Why or why not?$\left(1.2\right)$

In A Scandal in Bohemia, Sherlock Holmes receives a mysterious note. He states, "I have no data yet. It is a capital mistake to theorize before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts." What do you think Holmes meant?$(1.2)$

Write each of the following in scientific notation : $\left(1.5\right)$

a. $120 000$        b. $0.000 000 34$

c. $0.066$             d. $2700$

A bag of gumdrops contains 16 orange gumdrops, 8 yellow gumdrops, and 16 black gumdrops. $\left(1.4\right)$

a. What is the percentage of yellow gumdrops? Express your answer to the ones place. 

b. What is the percentage of black gumdrops? Express your answer to the ones place.

On the first chemistry test, $12$ students got As, $18$ students got Bs, and $20$ students got Cs. $\left(1.4\right)$

a. What is the percentage of students who received Bs?

    Express your answer to the ones place. 

b. What is the percentage of students who received Cs?

    Express your answer to the ones place.

For each of the following, indicate if the answer has a positive or negative sign:$\left(1.4\right)$
 a. Two negative numbers are added.
 b. A positive and negative number are multiplied.

For each of the following, indicate if the answer has a positive or negative sign: $\left(1.4\right)$

a. A negative number is subtracted from a positive number.

b. Two negative numbers are divided.

Classify each of the following statements as an observation or a hypothesis: $\left(1.2\right)$

a. A patient breaks out in hives after receiving penicillin.

b. Dinosaurs became extinct when a large meteorite struck  Earth and caused a huge dust cloud that severely decreased the amount of light reaching Earth.

c. The dash was run in  $9.8 s$.

Classify each of the following statements as an observation or a hypothesis: $\left(1.2\right)$

a. Analysis of $10$ ceramic dishes showed that four dishes contained lead levels that exceeded federal safety standards.
 b. Marble statues undergo corrosion in acid rain.
 c. A child with a high fever and a rash may have chickenpox.

Evaluate each of the following: $\left(1.4\right)$

a. $-95-\left(-11\right)=\_\_\_$.

b. $\frac{152}{-19}=\_\_\_$.

c. $4-56=\_\_\_$.

Evaluate each of the following: $\left(1.4\right)$

a.  $4\times \left(-8\right)=\_\_\_$.

b. $-12-48=\_\_\_$.

c. $\frac{-168}{-4}=\_\_\_$.

Identify each of the following as an observation, a hypothesis, 

an experiment, or a conclusion: $\left(1.2\right)$

a. . A patient has a high fever and a rash on her back.

b. A nurse tells a patient that her baby who gets sick after 

drinking milk may be lactose intolerant.

c. Numerous studies have shown that omega-3 fatty acids lower triglyceride levels.

Select the correct phrase(s) to complete the following statement: If experimental results do not support your hypothesis, you should: (1.2) 

a. pretend that the experimental results support your hypothesis 

b. modify your hypothesis 

c. do more experiments 

 Select the correct phrase(s) to complete the following statement: A hypothesis is confirmed when: (1.2)

a. one experiment proves the hypothesis 

b. many experiments validate the hypothesis 

c. you think your hypothesis is correct 

Which of the following will help you develop a successful study plan? (1.3)

 a. skipping class and just reading the text 

b. working the Sample Problems as you go through a chapter c. self-testing 

d. reading through the chapter, but working the problems later 

Which of the following will help you develop a successful study plan? (1.3) 

a. studying all night before the exam 

b. forming a study group and discussing the problems together 

c. working problems in a notebook for easy reference 

d. highlighting important ideas in the text