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When a pregnant woman ingests substances, the interaction of one substance with another often ______ the effects of one or both?

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IncreasesIn women that are pregnant, the effects of substances are far more adverse than they would be in a normal person, especially if the woman is taking more than one. For this reason, it is important for pregnant women to take as much care as possible of their bodies and refrain completely from smoking and drinking alcohol, as both of these activities are detrimental towards the fetus’s health. Pregnant women should even avoid second hand smoke from cigarettes.

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Which of the following would be considered a solution ? A salt in the sugar bowl B sugar added to water C oil added to water D any fat-soluble substance mixed with water soluble substance

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Which of the following would be considered a solution ? A salt in the sugar bowl B sugar added to water C oil added to water D any fat-soluble substance mixed with water soluble substance

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What kind of change occurs when salt dissolves in water a.) solution change b.) physical change c.) chemical change d.) substance change

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What kind of change occurs when salt dissolves in water a.) solution change b.) physical change c.) chemical change d.) substance change

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Like many forms of substance abuse, alcoholism develops through stages. Which of the following stages is the most advanced and the most difficult to recover from? abuse addiction dependenceLike many forms of substance abuse, alcoholism develops through stages. Which of the following stages is the most advanced and the most difficult to recover from? A. abuse B. addiction C. dependence

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Like many forms of substance abuse, alcoholism develops through stages. Which of the following stages is the most advanced and the most difficult to recover from? abuse addiction dependenceLike many forms of substance abuse, alcoholism develops through stages. Which of the following stages is the most advanced and the most difficult to recover from? A. abuse B. addiction C. dependence

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The chemical formula of lithium carbonate is Li2CO3. Which statement below best describes the types and number of atoms of each element making up this substance? A. Two lithium atoms; one calcium atom; one oxygen atom B. One lithium atom; three carbon atoms; three oxygen atoms C. One lithium atom; one carbon atom D. Two lithium atoms; one carbon atom; three oxygen atoms

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The chemical formula of lithium carbonate is Li2CO3. Which statement below best describes the types and number of atoms of each element making up this substance? A. Two lithium atoms; one calcium atom; one oxygen atom B. One lithium atom; three carbon atoms; three oxygen atoms C. One lithium atom; one carbon atom D. Two lithium atoms; one carbon atom; three oxygen atoms

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Which kind of substance accepts an electron pair? base hydroxide ion acid alkali

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Which kind of substance accepts an electron pair? base hydroxide ion acid alkali
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A person who has an insatiable craving for any substance

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A person who has an insatiable craving for any substance

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________________ are the body’s adverse reaction to introducing an excessive amount of a toxic substance into the system.

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Hangover

Hangover is unpleasant psychological and physiological effect experienced after consumption of alcohol such as distilled spirit and wine. Hangover usually developed after 6-8 hours and last or 24 hours. Furthermore, hangover, symptoms are related to blood alcohol concentration which is the amount of alcohol present in a person’s blood.

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In the carbon cycle, decomposition is the breakdown of a substance into simpler substances. What is the name for the process of the nitrogen cycle that produces ammonia?

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In the carbon cycle, decomposition is the breakdown of a substance into simpler substances. What is the name for the process of the nitrogen cycle that produces ammonia?

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A balance must exist between substance enetering and exiting cells.most animals remove substances by_.

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A balance must exist between substance enetering and exiting cells.most animals remove substances by_.

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Why is water an excellent solvent for most ionic compounds and polar covalent molecules but not for non-polar compounds? A) Water is a polar molecule. B) Water has a charge like an ion. C) Water is a deionizing substance. D) Water molecules have an unusually high kinetic energy in the liquid state.

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A)Water is a polar molecule. When talking about solubility, the rule that “like dissolves like” is usually correct. This means that polar substances are soluble in other polar substances. This occurs because the opposite partially charged ends of different polar molecules are attracted to each other. Similarly, the partially charged ends of polar molecules will be even more attracted to the charged ends of an ionic compound’s molecule. This is why,for example, table salt/ NaCl, which is an ionic compound, dissolves in water. 

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The weight of 10 identical samples of a substance is 0.1 pound. What is the weight of 1000 samples

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The weight of 10 identical samples of a substance is 0.1 pound. What is the weight of 1000 samples

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In 1987 the first substance to act as a superconductor at a temperature above that of liquid nitrogen (77 k) was discovered. the approximate formula of this substance is yba2cu3o7. calculate the percent composition by mass of this material.

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The molar mass of the elements are:

Yttrium (Y) = 88.91 g / mol

Barium (Ba) = 137.33 g / mol

Copper (Cu) = 63.55 g / mol

Oxygen (O) = 16 g / mol

 

Calculating for the molar mass of YBa2Cu3O7:

YBa2Cu3O7 = 88.91 + 2(137.33) + 3(63.55) + 7(16) = 666.22
g / mol

 

The masses of the elements in 1 mole of YBa2Cu3O7 are:

Yttrium (Y) = 88.91 g / mol (1 mole) = 88.91 g

Barium (Ba) = 137.33 g / mol (2 mole) = 274.66 g

Copper (Cu) = 63.55 g / mol (3 mole) = 190.65 g

Oxygen (O) = 16 g / mol (7 mole) = 112 g

 

We now calculate for the percent composition by mass of
each element:

% Y
= 88.91 g / 666.22 g = 13.35%


% Ba
= 274.66 g / 666.22 g = 41.23%


%Cu
= 190.65 g / 666.22 g = 28.62%


%O =
112 g / 666.22 g = 16.81%

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A substance that heats up relatively quickly has a

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Answer:

The correct sequence according to the question is steps- 4→1→3→5→6→2→7.

Explanation:

The given steps show that how the rocks are recycled from one form to another form due to certain factors like weathering over geological time scale which was explained by James Hutton and he termed this concept as the rock cycle.

The steps of the rock cycle in sequence according to the question are:

1.  Breakdown of rock by weathering into regolith- step 4

2.  Dumping and deposition of regolith in a reservoir- step  1

3.  Erosion and transportation of regolith by rain or wind- step  3

4. Cementing of the deposited layer to form sedimentary rock- step  5

5. Conversion of sedimentary rock to a metamorphic rock due to intense heat and pressure- step 6

6. Conversion of  metamorphic rocks to magma due to the melting of metamorphic rocks-
step 2

7. Conversion of magma to igneous rocks due to volcanic activities and cooling of magma-  step 7

Therefore sequence according to the question is steps- 4→1→3→5→6→2→7 is correct.

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An unknown substance has a mass of 56.8 g and a volume of 23.4 ml. what is the density of this unknown substance?

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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An unknown, rectangular substance measures 3.6 cm high, 4.21 cm long, and 1.17 cm wide. if the mass is 21.3 g, what is this substances density (in grams per milliliter)?

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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Lymph nodes produce what substance that assists in immunity from disease?

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The right answer is Transgenic organisms can produce a desired product that may benefit other organisms.

A transgenic organism contains DNA combining  stably integrated in all its cells. In other words, the organism, be it a plant, an animal or a microorganism, has a new piece of DNA embedded in it. a chromosome in each of its cells. This “new piece” of DNA usually contains a gene from another organism (plant, animal or other) that has been modified to be expressed in the new  organization. A transgenic organism may even possess the DNA of another organism of the same species. The inserted gene can be called the transgene.

Currently, diabetics are treated by injecting insulin from either a healthy human donor or cultures of genetically modified (transgenic) bacteria that secrete the protein.

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The weight of 10 identical samples of a substance is 0.1 pound. What is the weight of 100 samples?

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The weight of 10 identical samples of a substance is 0.1 pound. What is the weight of 100 samples?

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In order to observe a ______ property of a substance, the substance must interact with another substance , such as when gasoline burns or when sodium metal reacts with water

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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As a substance changes phase from a gas to liquid to solid: A- The spacing between molecules increases. B- It's density generally increases. C- The spacing between molecules is not affected. D- It undergoes chemical change.

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As a substance changes phase from a gas to liquid to solid: A- The spacing between molecules increases. B- It’s density generally increases. C- The spacing between molecules is not affected. D- It undergoes chemical change.

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At which point could the substance shown exist as a gas or a solid but not a liquid?

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Answer: The correct answer is all of these.

Explanation:

Organic compounds are defined as the chemical compounds where one or more carbon atoms are covalently bonded to other atoms of hydrogen, oxygen or nitrogen.

They occur naturally in nature and the main sources of these organic compounds are petroleum, coal and natural gases.

Petroleum are the naturally occurring substances which contain organic compounds in the form of gases, liquid or semi-solid. Thus, they are a major source of organic compound.

Coal is also a form of fossil fuel which are the major source of organic compound.

Natural gas contains hydrocarbons and also is the major source of organic compounds.

Thus, the correct answer is all of these.

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Iodine-123 is a radioactive substance used in medicine. It has a half-life of 13 hours. A nurse received a solution that initially contained 48 grams of iodine-123. Now only 12 grams of the iodine-123 remain. How many hours have passed since the nurse received the solution?

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Answer:

                The point that lie on the line is:

                        B.  (1,1)

Step-by-step explanation:

We are given that a line passes through the point (0,-1) and has a slope of 2.

We know that the equation of a line passing through (a,b) and having slope m is given by:

           y-b=m(x-a)

Here we have:  (a,b)=(0,-1) and m=2

This means that the equation of line is:

y-(-1)=2(x-0)\\y+1=2x\\y=2x-1

Now we will check which option is true.

A)

                (2,1)

when x=2

we have:

y=2times 2-1\\\y=4-1\\\y=3neq 1

Hence, option: A is incorrect.

B)

                     (1,1)

when x=1

we have:

y=2times 1-1\\\y=2-1\\\y=1

                Hence, option: B is correct.

C)

                      (0,1)

when x=0

we have:

y=2times 0-1\\\y=0-1\\\y=-1neq 1

Hence, option: C is incorrect.

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In which type of chemical bonding are electrons shared among all atoms in the substance?

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The balanced chemical reaction is as shown below,

                 N₂ + 3H₂  –> 2NH₃

The equation shows that every 3 moles of hydrogen, H2, there would be 2 moles of ammonia, NH3, that is going to be formed. Using this concept, we solve for the unknown in this item. 

Since we are restricted only of the number of hydrogen, it becomes our limiting reactant. 

          (6 moles H2) x (2 moles NH3/3 moles H2) = 4 moles NH3

Therefore, given enough amount of N2, the amount of NH3 that can be formed out of the 6 moles of H2 is equal to 4 moles. 

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Light waves will bend when passing from one transparent substance to another unless:

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Answer:

a) The time the police officer required to reach the motorist was 15 s.

b) The speed of the officer at the moment she overtakes the motorist is 30 m/s

c) The total distance traveled by the officer was 225 m.

Explanation:

The equations for the position and velocity of an object moving in a straight line are as follows:

x = x0 + v0 · t + 1/2 · a · t²

v = v0 + a · t

Where:

x = position at time t

x0 = initial position

v0 = initial velocity

t = time

a = acceleration

v = velocity at time t

a)When the officer reaches the motorist, the position of the motorist is the same as the position of the officer:

x motorist = x officer

Using the equation for the position:

x motirist = x0 + v · t (since a = 0).

x officer = x0 + v0 · t + 1/2 · a · t²

Let´s place our frame of reference at the point where the officer starts following the motorist so that x0 = 0 for both:

x motorist = x officer

x0 + v · t = x0 + v0 · t + 1/2 · a · t²      (the officer starts form rest, then, v0 = 0)

v · t = 1/2 · a · t²    

Solving for t:

2 v/a = t

t = 2 · 15.0 m/s/ 2.00 m/s² = 15 s

The time the police officer required to reach the motorist was 15 s.

b) Now, we can calculate the speed of the officer using the time calculated in a) and the  equation for velocity:

v = v0 + a · t

v = 0 m/s + 2.00 m/s² · 15 s

v = 30 m/s

The speed of the officer at the moment she overtakes the motorist is 30 m/s

c) Using the equation for the position, we can find the traveled distance in 15 s:

x = x0 + v0 · t + 1/2 · a · t²

x = 1/2 · 2.00 m/s² · (15s)² = 225 m

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6. A substance that enters Earth's cycles and does harm to living things is A. oxygen. B. hydrogen. C. freshwater. D. a pollutant.

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6. A substance that enters Earth’s cycles and does harm to living things is A. oxygen. B. hydrogen. C. freshwater. D. a pollutant.

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