A 194-g sample of caffeine (C3H10 N4O2) contains 6.02 x 10^23 molecules of
caffeine. If some energy drink contains 210. mg of caffeine, how many molecules of caffeine are present in the drink?
Answer:
6.52×10²⁰ molecules.
Explanation:
We'll begin by converting 210 mg of caffeine to grams (g). This can be obtained as follow:
Recall:
1 mg = 1×10¯³ g
Therefore,
210 mg = 210 mg / 1 mg × 1×10¯³ g
210 mg = 0.21 g
Therefore, 210 mg of caffeine is equivalent to 0.21 g of caffeine.
Finally, we shall determine the number of molecules in 0.21 g of caffeine as follow:
194 g of caffeine contains 602×10²³ molecules.
Therefore, 0.21 g of caffeine will contain = (0.21 × 602×10²³)/194 = 6.52×10²⁰ molecules.
Therefore 0.21 g contains 6.52×10²⁰ molecules.
Thus, we can say that 210 mg (i.e 0.21g) of caffeine contains 6.52×10²⁰ molecules.
Compounds and solutions are different because
A.only compounds are a form of matter.
B.compounds are pure substances while solutions are not.
C.a compound can be physically separated.
D.only compounds have uniform composition.
Answer:
only compound have uniform compositiob
Billy is running at a rate of 8 m/s West he ran a total distance of 400 m how long does it take him to complete the distance
Answer:
50 Seconds
Explanation:
400 Divided By 8 Is 50
Answer:
50
Explanation:
Its 50 because 400/8=50
A student measured the volume of water to be 18.5 ml; the actual volume was 17.5 ml. What was the % deviation
Answer:
+5.7%
Explanation:
18.5mL/17.5mL = 1.057 = 105.7% - 100% = 5.7%
Since the measured volume was higher, it is PLUS 5.7%
which of the following correctly described a compound
Answer:
We need the options to answer.
Explanation:
N/A
What is the main purpose of a leaf
Explanation:
for respiration(exchange of gases)
Actually, all leaves have the same structure. The main purpose is to carry the photosynthesis out, that provides food that needs to survive. :)
a knowledge of life science is essential for botanists, forest technicians ,park rangers and health care workers true or false
Answer: True
Explanation:
I took the test
Answer:
T
Explanation:
Trust i took the test :p
If this container of gas is heated,
then the pressure inside the container will
increase because pressure increases as
temperature increases.
Hypothesis
Theory
Law
Answer:
theory
Explanation:
kinetic theory of gases
Answer:
Hypothesis
Explanation:
Just did it
0.660 moles of NaCl are dissolved in 95.0 mL of water. Calculate the molarity of the NaCl solution. A) 62.7 M B) 0.069 M C) 6.95 M D) 0.0069 M
Answer:
C) 6.95 M.
Explanation:
Hello,
In this case, considering that the molarity is computed via the ratio of the moles of solute to the volume of the solution in liters:
[tex]M=\frac{n_{solute}}{V_{solution}}[/tex]
Since the volume here is 95.0 mL or also 0.0950 L, the molarity turns out:
[tex]M=\frac{0.660mol}{0.0950L} \\\\M=6.95 M[/tex]
Therefore, answer is C) 6.95M.
Best regards.
Ammonia reacts with diatomic oxygen to form nitric oxide and water vapor: 4 NH3 + 5 O2 → 4 NO + 6 H2O When 40.0 g NH3 and 50.0 g O2 are allowed to react, what is the mass of the remaining excess reagent?
Answer:
18.75 g of NH3.
Explanation:
The balanced equation for the reaction is given below:
4NH3 + 5O2 → 4NO + 6H2O
Next, we shall determine the masses of NH3 and O2 that reacted from the balanced equation.
This can be obtained as follow:
Molar mass of NH3 = 14 + (3x1) = 17 g/mol
Mass of NH3 from the balanced equation = 4 x 17 = 68 g
Molar mass of O2 = 16x2 = 32 g/mol
Mass of O2 from the balanced equation = 5 x 32 = 160 g
From the balanced equation above,
68 g if NH3 reacted with 160 g of O2.
Next, we shall determine the excess reactant. This can be obtained as follow:
From the balanced equation above,
68 g if NH3 reacted with 160 g of O2.
Therefore, 40 g of NH3 will react with = (40 × 160)/68 = 94.12 g of O2.
From the calculations made above, we can see that it will take a higher amount of O2 i.e 94.12g than what was given i.e 50g to react completely with 40 g of NH3.
Therefore, O2 is the limiting reactant and NH3 is the excess reactant.
Next we shall determine the mass of excess reactant that reacted. This can be obtained as follow:
From the balanced equation above,
68 g if NH3 reacted with 160 g of O2.
Therefore, Xg of NH3 will react with 50 g of O2 i.e
Xg of NH3 = (68 × 50)/160
Xg of NH3 = 21.25 g
Therefore, 21.25 g of NH3 (excess reactant) were consumed in the reaction.
Finally, we shall determine mass of the remaining excess reactant as follow:
Mass of excess reactant = 40 g
Mass of excess reactant that reacted = 21.25 g
Mass of excess reactant remainig =?
Mass of excess reactant remainig = (Mass of excess reactant) – (Mass of excess reactant that reacted)
Mass of excess reactant remainig
= 40 – 21.25
= 18.75 g
Therefore, the mass of excess reactant remaining is 18.75 g of NH3.
Convert 355 km/s into mm/s.
Answer:
the answer would be, 355000 mm/s.
Give the names of the cation in each of the following compounds: a. CuS b. Ag2SO4 c. Al(ClO3)3 d. CO(OH)2 e. PbCO3.
Answer:
a. Cu2+ (Copper (II) ion ) b. 2Ag+ ( Silver ion) c. Al3+ (Aluminium (III) ion) d. Co2+ ( Cobalt (II) ion) e. Pb2+ ( Lead (II) ion )
Explanation:
Cations are positively charged ions.
In the question given;
CuS , known as Copper (ii) Sulphide, has Cu2+ (Copper (II) ion ) as the Cation.
Ag2SO4, Known as Silver Sulfate, has 2Ag+ ( Silver ion) as the Cation.
Al(ClO3)3, known as Aluminium Chlorate, has Al3+ (Aluminium (III) ion), as the Cation.
Co(OH)2, known as Cobalt(II) Hydroxide, has Co2+ ( Cobalt (II) ion) , as the Cation.
PbCO3, known as Lead(II) Carbonate, has Pb2+ ( Lead (II) ion ), as the Cation.
The solar wind is made up of ions, mostly protons, flowing out from the Sun at about 400 km/s. Near Earth, each cubic kilometer of interplanetary
space contains, on average, 6 x 10^15 solar-wind ions.
How many miles of ions are in a cubic kilometer of near- Earth space?
Answer:
There are [tex]6\times 10^{12}[/tex] miles of ions in a cubic kilometer of near-Earth space.
Explanation:
In this context, we must be clear on stating that words miles is a synonym for thousands. In other words, the question may be rewritten to this form: How many thousand of ions are in a cubic kilometer of near-Earth space? In engineering notation, a thousand is represented by:
[tex]x = 10^{3}[/tex]
As we know the average quantity of solar-wind ions in a cubic kilometer of interplanetary space near Earth, we need to make quick conversion to determine the quantity of miles of ions by this formula:
[tex]y = n\cdot 10^{-3}[/tex]
Where:
[tex]n[/tex] - Quantity of solar-wind ions, measured in units.
[tex]y[/tex] - Quantity of solar-wind ions, measured in thousands (or miles).
If we know that [tex]n = 6\times 10^{15}\,units[/tex], then:
[tex]y = (6\times 10^{15}\,units)\cdot \left(10^{-3}\,\frac{miles}{unit} \right)[/tex]
[tex]y = 6\times 10^{12}\,miles[/tex]
There are [tex]6\times 10^{12}[/tex] miles of ions in a cubic kilometer of near-Earth space.
During your future endeavors in chemistry you will inevitably do a bunch of acid-base problems. Of the strong bases above, calcium hydroxide, strontium hydroxide, and barium hydroxide often trick students into making small mistakes. Why do you think that is the case? a. There is only half a mole of hydroxide per mole of compound. b.They are actually acidic rather than basic. c. Nothing special about these, all acid-base is confusing! d. There are two moles of hydroxide for each mole of these compounds.
Answer:
d. There are two moles of hydroxide for each mole of these compounds.
Explanation:
calcium hydroxide, strontium hydroxide, and barium hydroxide all have two hydroxide compunds. the difference between each of these compounds is they all contain a different element along with hydroxide.
What are non-examples of a nucleus
Answer:n a red blood cell, the control center is the nucleus. A mitochondria is not a nucleus. It is another organelle that produces energy for the cell.
Explanation:
Compound A, C7H13Br, is a tertiary alkyl bromide. On treatment with CH3CH2ONa, A is converted into B, C7H12. Ozonolysis of B with O3 gives C as the only product. What are the structures of compounds A and B
Answer:
Compound A: 1-bromo-1-methylcyclohexane
Compound B: 1-methylcyclohex-1-ene
Explanation:
In this question, we can start with the I.D.H (hydrogen deficiency index):
[tex]I.D.H~=~\frac{(2C)+2+(N)-(H)-(X)}{2}[/tex]
In the formula we have 7 carbons, 13 hydrogens, and 1 Br, so:
[tex]I.D.H~=~\frac{(2*7)+2+(0)-(13)-(1)}{2}=1[/tex]
We have an I.D.H value of one. This indicates that we can have a cyclic structure or a double bond.
We have to keep in mind that the Br atom must be bonded to a tertiary carbon. We can not have a double bond because in the ozonolysis reaction we have only 1 product, therefore, we can not have a double bond in the initial molecule (if we have a double bond in the initial molecule we will have more than 1 product in the ozonolysis reaction).
With this in mind, we will have a cyclic structure. If we have 7 carbons and we need a tertiary alkyl halide. We can have a cyclic structure of 6 members and a methyl group bonded to a carbon that also is bonded to a Br atom (1-bromo-1-methylcyclohexane).
In the reaction with [tex]CH_3CH_2ONa[/tex] we will have an elimination reaction. In other words, we have the production of a double bond inside of the cyclic structure (1-methylcyclohex-1-ene).
See figure 1 for further explanations.
I hope it helps!
earthquakes are most common
Answer:
Most earthquakes occur along the edge of the oceanic and continental plates.
Explanation:
And if your question is for the country then it will be Japan
Which of the following statements would be the hypothesis most easily tested? a) Oak trees grow tallest between temperatures of 10 and 40 degrees Celsius. b) All organisms are made of cells c) An invertebrate is an animal without a backbone or an internal skeleton d) If life were to exist on another planet, that life would also be composed of carbon compounds.
Answer: a) Oak trees grow tallest between temperatures of 10 and 40 degrees
Explanation:
This hypothesis is specific, can be tested (though perhaps not easily), and is well set up.
Hope this helps! :)
A hot needle sinks when put on the surface of cold water. Will a cold needle float or sink in warm water?
Answer:
sink
Explanation:
The Intermolecular force of attraction exists within the water molecule. This type of intermolecular force of attraction is known as a hydrogen bond. A hydrogen bond is a dipole-dipole intermolecular attraction that occurs when hydrogen is covalently bonded to highly electronegative elements of a small atomic size.
When the heat is applied to this intermolecular force, the heat disrupts the intermolecular force, and the surface tension is being broken. This is what caused a hot needle to sink when placed in cold water. But when a cold needle is placed on the surface of warm water, the cold needle will not break up the warm water's surface tension. As a result, the cold need sinks in the warm water.
1. What are the 5 senses you use
during the 1st step Scientific
Method observation?
Answer:
Sight, hearing, taste, touch, and smell
Explanation:
Sort these molecules into the appropriate bin according to their polarity.Drag the appropriate items to their respective bins.HBr CO2 BF3 H2 CH4 NH3Polar Non polar
Explanation:
Generally, polar molecules contain polar bonds that arise as a result of the difference in electronegativities of the elements in the molecule. In most instances, molecules containing a metal and a non metal are polar in nature.
HBr - This molecule has two opposite sides of polarity, a group 1 and group 7 element. It is polar
CO2 - The bond between C and O is polar however, there is a cancellation of the polar bonds due to how the atoms are arranged. It is non polar.
BF3 - There is no net dipole (separation of charges) in this compound hence it is non polar.
H2 - Covalent molecules made up of only one type of atom are non polar.
CH4 - This is non polar as the difference in electronegativities between C and H is not great enough to form a dipole.
NH3 - The polar bonds (N-H) do not cancel each other out. Hence this molecule is polar.
Neil Bohr's model of the atom suggested that electrons are found in distinct paths. Question 11 options: True False
Answer:
true
Explanation:
A student was asked to separate a mixture of chemicals. The weight of each component within the mixture is as follows: potassium bromide 2.53g and 0.760g barium sulfate. What is the percentage of barium sulfate within the mixture?
Answer:
a
Explanation:
f
The percentage of barium sulphate within the mixture is 23.1 %.
We have a mixture of barium sulfate and potassium bromide.
We have to determine the percentage of barium sulfate within the mixture.
What is a Mixture ?A mixture is a material made up of two or more different chemical substances which are not chemically bonded to one another.
According to the question -
Mass of barium sulfate = 0.760 g
Total mass of mixture = 0.760 + 2.53 = 3.29 g
Therefore, the percentage of barium sulfate within the mixture -
0.760/3.29 x 100 = 23.1 %
Hence, the percentage of barium sulphate within the mixture is 23.1 %.
To solve more questions on Percentage composition, visit the link below-
https://brainly.com/question/18184070
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100. cal of heat are added to 18.0 g of ethanol (0.581 cal/g °C) originally at 23 °C. The final temperature is ____________.
Answer:
Final temperature is 32.56 °C
Explanation:
The specific heat of a substance is the amount of heat required to raise the temperature of 1g of the substance by 1°C.
The following equation/formula is used;
Q = m × c × ΔT
Where; Q= amount of heat supplied
(cal)
M= mass of ethanol (g)
C= specific heat of ethanol
(cal/g °C)
ΔT= change in temperature (°C)
i.e. (final temperature - initial
temperature)
According to the question, Q= 100 calories (cal), M= 18g, C= 0.581 cal/g °C, initial temperature = 23°C, final temperature = ?
Hence, we insert our values into the equation;
Q = m × c × ΔT
ΔT = Q/mc
(Final T - Initial T) = Q/mc
(Final T - 23) = 100/ 18 × 0.581
(Final T - 23) = 100/10.458
Final T - 23 = 9.562
Final T = 23 + 9.562
Final T = 32.562
Hence, the final temperature of ethanol is 32.56°C
A student measures the mass of an 11.2cm3 block of sugar to be 17.8 g. What is the density of the sugar?
Answer:
21 cm 3 that is the answer
a person loses 2.70 lb in two weeks. how many grams did they lose?
Answer:
1224.7
Explanation:
Each lb is 453.59
Based on the conversion factor, a person loses 2.70 lb in two weeks loses 1225.8 g
How can we concer from pounds, lb to grams?The conversion factor from pounds to grams is given as follows:
1 pound = 454 gTherefore, 2.70 pounds can be converted to grams as follows:
270 lb = 2.70 × 454 g/ 1 lb
270 lb = 1225.8
Thus, a person loses 2.70 lb in two weeks loses 1225.8 g
Learn more about pounds and grams at: https://brainly.com/question/1121265
What should the ^14_6C content (in percent of y0) of a fossilized tree that is claimed to be 3000 years old?
Answer:
The current mass fraction of [tex]^{14}_{6} C[/tex] should be approximately 68.8 percent.
Explanation:
[tex]^{14}_{6} C[/tex] is a radioactive isotope with a halflife of 5568 years. The decay of any radioisotope is modelled after the following ordinary differential equation:
[tex]\frac{dm}{dt} = -\frac{m}{\tau}[/tex]
Where:
[tex]m[/tex] - Current mass of the isotope, measured in grams.
[tex]\tau[/tex] - Time constant, measured in years.
The solution of this equation is of the form:
[tex]m(t) = m_{o}\cdot e^{-\frac{t}{\tau} }[/tex]
Where:
[tex]t[/tex] - Time, measured in years.
[tex]m_{o}[/tex] - Initial mass of the isotope, measured in grams.
The time constant can be found as a function of halflife ([tex]t_{1/2}[/tex]):
[tex]\tau = \frac{t_{1/2}}{\ln 2}[/tex]
If [tex]t_{1/2} = 5568\,yrs[/tex] and [tex]t = 3000\,yrs[/tex], the mass fraction of [tex]^{14}_{6} C[/tex] is:
[tex]\tau = \frac{5568\,yrs}{\ln 2}[/tex]
[tex]\tau \approx 8032.926\,yrs[/tex]
[tex]\frac{m(3000\,yrs)}{m_{o}} = e^{-\frac{3000\,yrs}{8032.926\,yrs} }[/tex]
[tex]\frac{m(3000\,yrs)}{m_{o}} \approx 0.688[/tex]
The current mass fraction of [tex]^{14}_{6} C[/tex] should be approximately 68.8 percent.
Given the ion C2O4-2- , what species would you expect to form with each of the following ions?1. K+ _____2. Cu2+_____3. Bi3+_____4. Pb4+______5. NH4+______6. H+______
Answer:
1. K₂C₂O₄
2. CuC₂O₄.
3. Bi₂(C₂O₄)₃
4. Pb(C₂O₄)₂.
5. (NH₄)₂C₂O₄
6. H₂C₂O₄
Explanation:
Hello,
In this case, since the oxidation states are exchanged according to the naming rules, the resulting species are shown below:
1. K₂C₂O₄
2. CuC₂O₄ (here, the +2 of copper and -2 of C₂O₄, are simplified).
3. Bi₂(C₂O₄)₃
4. Pb(C₂O₄)₂ (here, the +4 of lead and -2 of C₂O₄, are simplified).
5. (NH₄)₂C₂O₄
6. H₂C₂O₄
Regards.
WORTH A LOT OF POINTS! just copy what on the picture for notes so i can copy and paste i do not feel like writing all of that down
Answer:
A base pair is a pair of bases that form hydrogen bonds in the double stranded DNA molecule.
- Adenine-thymine: A-T
- Guanine-cytosine: G-C
Replication Process:
- Double strand unwinds.
- New nucleorides line up via base pairing.
- Colvalent bonds link nucleotides together in the new strands.
Explanation:
Calculate the kinetic energy, in joules of a 1250-kg automobile moving at 20.0 m/s.
Answer:
250000 J.
Explanation:
From the question given above, the following data were obtained:
Mass (m) = 1250 kg
Velocity (v) = 20.0 m/s.
Kinetic energy (K.E) =?
Kinetic energy is simply defined as energy possed by a body in motion. Mathematically, it is expressed as:
K.E = ½mv²
Where:
K.E is the kinetic energy
m is the mass of the object
v is the velocity of the object.
Thus, we can obtain the kinetic energy of the automobile by using the above formula as illustrated below:
Mass (m) = 1250 kg
Velocity (v) = 20.0 m/s.
Kinetic energy (K.E) =?
K.E = ½mv²
K.E = ½ × 1250 × 20²
K.E = 625 × 400
K.E = 250000 J
Therefore, the kinetic energy of the automobile is 250000 J