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A second reaction mixture was made up in the following way: 10 mL 4.0 M acetone + 20 mL 1.0 M HCl + 10 mL 0.0050 M I2 + 10 mL H2O a. What were the initial concentrations of acetone, H+ ion, and I2 in the reaction mixture? (acetone) ___________ M; (H+) ___________ M; (I2)0 ___________ M b. It took 120 seconds for the I2 color to disappear from the reaction mixture when it occurred at the same temperature as the reaction in Problem 2. What was the rate of the reaction?

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A. We can calculate the initial concentrations of each by
the formula:

initial concentration ci = initial volume * initial
concentration / total mixture volume

where,

total mixture volume = 10 mL + 20 mL + 10 mL + 10 mL = 50
mL

ci (acetone) = 10 mL * 4.0 M / 50 mL = 0.8 M

ci (H+) = 20 mL * 1.0 M / 50 mL = 0.4 M               (note: there is only 1 H+ per 1 HCl)

ci (I2) = 10 mL * 0.0050 M / 50 mL = 0.001 M

 

B. The rate of reaction is determined to be complete when all of I2 is consumed. This is signified by complete disappearance of I2 color
in the solution. The rate therefore is:

rate of reaction = 0.001 M / 120 seconds

rate of reaction = 8.33 x 10^-6 M / s

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A certain skin lotion is a fine mixture of water and various oils. This lotion is cloudy and cannot be separated into oil and water by filtration. Moreover, its components do not separate when left standing. What type of mixture is it? solution suspension colloid compound NextReset

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The answer is: colloid.

In the presence of an emulsifying agent, a mixture of oil and water becomes a colloidal dispersion.

Colloidal dispersion (colloid) is a system, in which discrete particles, droplets or bubbles of a dispersed phase (in this case oil), whose size at least in one dimension is in the range from 1 to 1000 nm are distributed in the other, usually continuous phase – dispersion medium (in this case water) differing from the dispersed phase in composition or state of aggregation.

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A second reaction mixture was made up in the following way: 10 mL 4.0 M acetone + 20 mL 1.0 M HCl + 10 mL 0.0050 M I2 + 10 mL H2O a. What were the initial concentrations of acetone, H+ ion, and I2 in the reaction mixture? (acetone) ___________ M; (H+) ___________ M; (I2)0 ___________ M b. It took 120 seconds for the I2 color to disappear from the reaction mixture when it occurred at the same temperature as the reaction in Problem 2. What was the rate of the reaction?

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A. We can calculate the initial concentrations of each by
the formula:

initial concentration ci = initial volume * initial
concentration / total mixture volume

where,

total mixture volume = 10 mL + 20 mL + 10 mL + 10 mL = 50
mL

ci (acetone) = 10 mL * 4.0 M / 50 mL = 0.8 M

ci (H+) = 20 mL * 1.0 M / 50 mL = 0.4 M   (note: there is only 1 H+ per
1 HCl)

ci (I2) = 10 mL * 0.0050 M / 50 mL = 0.001 M

 

B. The rate of reaction is determined to be complete when
all of I2 is consumed. This is signified by complete disappearance of I2 color
in the solution. The rate therefore is:

rate of reaction = 0.001 M / 120 seconds

rate of reaction = 8.33 x 10^-6 M / s

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In which situation can a mixture always be called a solution

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In which situation can a mixture always be called a solution

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The process of pouring a mixture through a filter to catch the large particles while allowing the smaller particles to pass through and collect beneath

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25) Answer is: less metallic and more nonmetallic.

Electronegativity increases from left to right across a period, atoms have tendency to attract electrons.

Electronegativity (χ) is a property that describes the tendency of an atom to attract a shared pair of electrons.

26) Answer is: radioisotope.

Radioisotope has an unstable atomic nucleus and emit energy and particles when it changes to a more stable form.

Francium (Fr) is element with atomic number 87 (87 protons and 87 electrons).

27) Answer is: boils.

Boiling is the temperature at which the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere.

The Celsius scale was based on 0°C for the freezing point of water and 100°C for the boiling point of water at 1 atm pressure.

28) Answer is: endothermic.

There are two types of reaction:  

1) endothermic reaction (chemical reaction that absorbs more energy than it releases, ΔH>0).

2) exothermic reaction (chemical reaction that releases more energy than it absorbs).  

For example, the breakdown of ozone is an endothermic process. Ozone has lower energy than molecular oxygen (O₂) and oxygen atom, so ozone need energy to break bond between oxygen atoms.  

29) Answer is: kinetic.

The average kinetic energy of molecules depends on the temperature.  

As temperature increases, molecules gain more energy from surrounding and move faster.  

Kinetic energy (standard unit is the joule J) depends on speed of the molecule.  

Solid gains kinetic energy to become a liquid and then becomes a gas.

30) Answer is: alpha particles.

This was famous Rutherford’s Gold Foil Experiment: he bombarded thin foil of gold with positive alpha particles.

Rutherford observed the deflection of alpha particles on the photographic film.  

Alpha particles are helium atom particles, consist of two protons and two neutrons.  

According to Rutherford model of the atom: atoms have their charge concentrated in a very small nucleus.  

31) Answer is: highest.

For example, calcium oxide.

Calcium oxide (CaO) has ionic bonds between calcium cations (Ca²⁺) and oxygen anions (O²⁻).

Because it has strong ionic bonds, it has high melting point (around 2600°C).

Ionic bond is the electrostatic attraction between oppositely charged ions (cations and anions).

32) Answer is: a scientific model.

A scientific model is a representation of an idea, an object, a process or a system that is used to describe and explain phenomena that cannot be experienced directly.

33) Answer is: the superscript is mass number and the subscript is atomic number.

Atomic number(Z) is the number of protons, which is characteristic of a chemical element..

Mass number (A) is the total number of protons and neutrons in a nucleus.

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Is copper sulfate a mixture

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1.      A.

It is a technique typically engaged in electrical power and electronic devices, wherein the devices are run at less than their rated maximum power degeneracy, taking into account the case or body temperature, the ambient temperature and the type of cooling mechanism used.

2.      B.

In order to answer the question, you need to know the area of a circle.
Area = pi * r^2
Area = 3.14 * (100/2) ^ 2
Area = 3.14 * 50^2
Area = 7850 mils^2 = 0.00785 in^2

3.      A.

V / 15 A = 0.213 Ohm 
0.213 Ohm / 125 ft * 1000 ft = 1.71 Ohm / 1000 ft 
Closest gauge is #12 AWG (solid wire) 
#12 is 1.588 Ohm / ft, which is a 2.9775 V drop @ 15A

4.      A.

RHW cale insulation can be used up to 167 degrees F.

5.      D.

This is a type of electrical connector used to fasten two or more low-voltage (or extra-low-voltage) electrical conductors.

6.      C. the ease with which a material allows electricity to move is called CONDUCTIVITY

7.      D.

Stranded conductors are not acceptable in the pressure terminals of a duplex receptacle. Aluminum conductors of suitable gauge for a 15 ampere duplex outlet will not fit in the pressure terminal holes. 

8.      D.

A 3/0 AWG THHN insulated Copper is rated at 225 amps and it falls under the 90 degree C table.

9.      D.

A #12 copper conductor with an insulation factor of 90 degrees C is rated at 20 amps. A #12 aluminum conductor with an insulation rating of 90 degrees C is rated at 15 amps. These conductors ratings only applies to three conductors in a rated at 15 amps. These conductors’ ratings only applies to three conductors in a raceway. From 7 to 24 conductors in a raceway, both aluminum and copper conductor’s ratings have to be reduced by .70, so 15 amps x .7 = 10.5 amps and 20 amps x .7 = 14 amps respectively.

10.  A.

NEC 310.15(B)(1) and (2), table 310.15(B)(2)(a), and table 310.15(B)(17).
Convert 158°F to C result is 70°C. 50 amps x .33 correction factor = 16.5 amps

11.  A.

12.  B.

Ideally, nm or armored cable should be installed in a wall stud at least 1 1/4 inches from the front edge of the stud.

13.  C.

Always use flux for electrical connections and never use acid flux on electrical connections

14.  D.

In wire gauge, the lower the number, the larger the diameter. So a 6 gauge is larger than 12 gauge, but smaller than 4 gauge.

15.  A.

16.  D.

17.  C.

Table 310-16 NEC

18. 
MCM means 1000’s (M) of (C)ircular (M)ils

19.  D.

Rubber tape is used to round sharp edges

20.  B.

The larger the diameter, the larger the ampacity, or the ability to carry current.

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Milo wants to make a mixture that is 50% lemon juice and 50% lime juice. How much 100% lemon juice should he add to a juice that is 20% lemon juice and 80% lime juice to make 4 gallons of the 50% lemon/50% lime juice mixture?

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The triangle ABC is similar to triangle LMP. The order here is very important. The letters correspond to one another
A corresponds to L (first letters of each sequence) 
B corresponds to M (second letters of each sequence)
C corresponds to P (third letters of each sequence)

In a similar fashion, the segments also correspond to one another. 
AB corresponds to LM (first two letters of each sequence)
AC corresponds to LP (first and last letters of each sequence)
BC corresponds to MP (last two letters of each sequence)

————————————

AB corresponds to LM. AB is 4 units long. LM is 2 units long. So AB is twice as long as LM. This ratio (of 2:1) will be applied to every paired corresponding value.

Also, the right angle is at angle M for triangle LMP. The right angle will be at angle B for triangle ABC (since B corresponds to M). The answer will have an x coordinate of 7. So the answer is either choice B or choice C.

If we move 4 units down from point B, we land on (7,-10). That isn’t listed as an answer choice. Let’s try moving 4 units up from point B. We land on (7,-2). This is an answer choice

So the final answer is choice C) (7,-2)

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Zinc and magnesium metal each reacts with hydrochloric acid to make chloride salts of the respective metals, and hydrogen gas. a 11.20-g mixture of zinc and magnesium produces 0.6854 g of hydrogen gas upon being mixed with an excess of hydrochloric acid. determine the percent magnesium by mass in the original mixture.

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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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If you combine 240.0 mL of water at 25.00 °C and 120.0 mL of water at 95.00 °C, what is the final temperature of the mixture? Use 1.00 g/mL as the density of water.

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The equation for how temperature changes the resistance R is: 

R=R₀(1+α(T-T₀)), where R₀ is the resistance at T₀=20°C, T is the temperature for which we want to calculate the resistance and α is the temperature coefficient for resistance. 

The resistance of the copper wire increases by 18% or by 0.18, so the new value for the resistance is R=1.18*R₀.

T₀=20°C
=0.0068
R=1.18*R₀

Now we need to input that into the equation for resistance change and solve for temperature T.  

1.18R₀=R₀(1+α(T-20)), R₀ cancels out,

1.18=1+α(T-20),

1.18-1=α(T-20), we divide by α,

0.18/α=T-20, we put 20 on the left side,

26.47+20=T

T=46.47°C

So the temperature on which the resistance of copper wire will increase by 18% is T=46.47°C. 

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A metal smith pours 3.00 kg of lead shot at 99oc into 1.00 kg of water at 25oc in an isolated container. what is the final temperature of the mixture?

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The equation for how temperature changes the resistance R is: 

R=R₀(1+α(T-T₀)), where R₀ is the resistance at T₀=20°C, T is the temperature for which we want to calculate the resistance and α is the temperature coefficient for resistance. 

The resistance of the copper wire increases by 18% or by 0.18, so the new value for the resistance is R=1.18*R₀.

T₀=20°C
=0.0068
R=1.18*R₀

Now we need to input that into the equation for resistance change and solve for temperature T.  

1.18R₀=R₀(1+α(T-20)), R₀ cancels out,

1.18=1+α(T-20),

1.18-1=α(T-20), we divide by α,

0.18/α=T-20, we put 20 on the left side,

26.47+20=T

T=46.47°C

So the temperature on which the resistance of copper wire will increase by 18% is T=46.47°C. 

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When elements that form a mineral dissolve in hot water, they form a mixture called a(n) ______.

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When elements that form a mineral dissolve in hot water, they form a mixture called a(n) ______.

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The nurse cares for the client receiving dopamine hydrochloride at 4 mcg/kg/minute. the nurse determines the client weighs 64 kg. the nurse uses a dopamine mixture of 1.6mg/ml. the nurse should set the iv pump at which rate?

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The Right BMI is 17.62 which is B. and he is slightly in underweight

To calculate the BMI simply put the figures given in the statement in the given formulate

BMI = Weight (in pounds) × 703 / [Height (in inches)] ² = 130 × 703 / [72] ² Which will give us 17.62.

* The body mass index (BMI) is a tool to estimate a person’s body size. Invented by Adolphe Quételet, this index is also called the Quételet index.

* It is calculated according to the size and the body mass. It was originally designed for adults aged 18 to 65, but new patterns of growth have emerged in recent decades for children aged 0 to 18 years. In both cases, it is an indication and is involved in the calculation of the fat mass index (IMG).

* The values 18 and 25 are commonly accepted benchmarks for a normal BMI and therefore have a risk ratio deemed acceptable. Our patient is slight under 18 (17.62), so he need to gain some pounds.

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Gabrielle is making a mixture of compost and soil to use for a special plant. he wants his Final Mix to be 2 parts compost to 10 Parts potting soil. He wants to end up with 12 kg of mix. How many kilograms of compost should Gabrielle use?

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Gabrielle is making a mixture of compost and soil to use for a special plant. he wants his Final Mix to be 2 parts compost to 10 Parts potting soil. He wants to end up with 12 kg of mix. How many kilograms of compost should Gabrielle use?

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Which of the following best describes the difference between a mixture and a pure substance? A. A mixture is made up of only one type of atom; a pure substance is made up of more than one type of atom. B. A mixture has different properties throughout; a pure substance has the same properties throughout. C. A mixture has the same properties throughout; a pure substance has the different properties throughout. D. A mixture is made up of more than one type of atom; a pure substance is made up of only one type of atom.

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The type of plants that you can expect to see growing first after the flood are small annual plants.


Explanation:

There are two types of ecological succession, primary and secondary ecological succession. These two successions are created by different factors. A success that is produced by the flood is a secondary succession. A secondary succession refers to a type of succession in which an earlier built ecosystem is demoted to a smaller population of species. For this type of succession, the soil is already present and the seeds, roots and vegetative parts of some of the damaged plants may survive. Thus, secondary succession is normally quicker than primary succession, which average start out on bare lands or rocks. The pioneer species for small succession are annual plants, followed by shrubs and then pine and oaks. The pioneer specie for the primary sequence is lichen, which has the strength to grow where there is no soil.

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Is honey a Pure substance or a mixture? Please answer ASAP i have 3 exams coming up in scince. HELP!!!

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This is actually really is. Notice how the protons + the neutrons equal the top number next to the element and the bottom one is the amount of protons. 

So for Rn, it already gives you the protons and the atomic number (the top number), you just subtract them —> 209-86= 123 neutrons.

I don’t have a periodic table to look at, but for the next one just add the protons and the neutrons to get the atomic number (the atomic number will be under the element symbol) and look for it on the periodic table to find the element and so on. 

I hope this helps ♥

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This question is based on the following paragraph. The sentences are numbered to help you answer the question. (1) Making rice pudding can be very easy. (2) First, get a large, heavy saucepan. In the pan, measure 3 cups of whole milk, 1 cup of water, 1/2 stick of margarine or butter, and 1/2 cup of rice. (3) Bring this mixture to a quick boil. (4) Lower heat and slowly simmer for 45 minutes. (5) Remove the saucepan from the heat. (6) Add one beaten egg, 1/2 cup of sugar, and 1/2 teaspoon of vanilla. (7) Stir well. (8) Serve warm or cold. (9) Enjoy your treat. The topic sentence of this paragraph is A. Sentence 2. B. Sentence 3. C. Sentence 1. D. Sentence 4. PLEASE HELP!

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The correct answer is B. The story contains a moral.

Explanation:

In literature, parables are usually short didactic stories that include human characters in “real-life” situations that are used to convey a specific moral or lesson about life, behavior, beliefs, etc. This type of literary work is quite similar to fables, but in fables, animals and not humans are the main characters. Additionally, parables are common to depict religious morals or values, although they can be used to convey morals that are not related to religion. Considering this, the sentence that best describes a characteristic of a parable is the story contains a moral, because this is the main purpose of any parable.

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A sugar mixture has 3 parts water and 2 parts sugar. Suppose the chef adds one more part to each. What is the new ratio of sugar to water?

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Answer:

B. Quadrant II or III

Step-by-step explanation:

We know that, the first part of the question is ‘In which quadrant would you find the point P if the co-ordinates are (-5, .. ‘

Assuming, we are talking about x-y axis where the point P is not on the axis.

The only possibility for the x co-ordinate to be -5 is if the point lies in the 2nd or 3rd quadrant.

for e.g. In 2nd quadrant, the point can be (-5,3) and in 3rd qudrant the point can be (-5,-4).

Hence, option B is correct.

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How is separating a compound more complicate that separating parts of a mixture

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How is separating a compound more complicate that separating parts of a mixture
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