Answers
Answer:
3 i am pretty sure make me brainy i gust
Explanation:
Related Questions
Molarity and Dilution
How many moles are needed in a 100. mL solution of a 0.10M CuSO4 5H2O solution?
Answers
Answer: The moles needed are 0.01.
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
[tex]Molarity=\frac{n\times 1000}{V_s}[/tex]
where,
n = moles of solute [tex](CuSO_4.5H_2O)[/tex] = ?
[tex]V_s[/tex] = volume of solution in ml
Now put all the given values in the formula of molarity, we get
[tex]0.10=\frac{n\times 1000}{100}[/tex]
[tex]n=\frac{0.10\times 100}{1000}=0.01[/tex]
Therefore, the moles needed are 0.01.
Which of the following describes an exothermic reaction?
Answers
An exothermic reaction is described by ΔH(reactants) is greater than ΔH( products) and the correct option is option A.
What is Exothermic reaction?The word exothermic means “releasing heat.” Energy, often in the form of heat, is released as an exothermic reaction proceeds.
Enthalpy of a reaction is defined as the heat energy change (Δ H) that takes place when reactants go to products. If heat is absorbed during the reaction, Δ H is positive; if heat is released, then Δ H is negative.
ΔH value negative –> energy released –> exothermic reaction
ΔH value positive –> energy absorbed –> endothermic reaction
Therefore, an exothermic reaction is described by ΔH(reactants) is greater than ΔH( products) and the correct option is option A.
Learn more about Exothermic reactions, here:
https://brainly.com/question/10373907
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In an isolated system, mass can neither be
created or destroyed.
ube
FALSE
TRUE
Answers
Answer:
True
Explanation:
The law of conservation of mass states that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations. According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants.
Hope it helps
A 334 mL sample of hydrogen was collected over water at 23C on day when the atmospheric pressure was 756 mm Hg.The vapor pressure of water under these conditions is 17.54 mm Hg. What volume, in liters, will the dry hydrogen ( No water vapor) occupy at STP?
Answers
Answer:
0.299 L
Explanation:
We'll begin by calculating the pressure of dry gas. This can be obtained as follow:
Measured pressure = 756 mm Hg
Water vapor pressure = 17.54 mm Hg
Pressure of dry gas =?
Pressure of dry gas = (Measured pressure) – (Water vapor pressure)
Pressure of dry gas = 738.46 mmHg
Finally, we shall determine the volume occupied at STP. This can be obtained as follow:
Initial volume (V₁) = 334 mL = 334 / 1000 = 0.334 L
Initial pressure (P₁) = 738.46 mmHg
Initial temperature (T₁) = 23 °C = 23 °C + 273 = 296 K
Final pressure (P₂) = 760 mmHg
Final temperature (T₂) = 273 K
Final volume (V₂)
P₁V₁/T₁ = P₂V₂/T₂
738.46 × 0.334 / 296 = 760 × V₂/273
Cross multiply
296 × 760 × V₂ = 738.46 × 0.334 × 273
224960 × V₂ = 67334.2597
Divide both side by 224960
V₂ = 67334.2597 / 224960
V₂ = 0.299 L
Thus, the volume of the dry gas st STP is 0.299 L.
5. What kind of model is represented in the image below?"
A. mathematical
B. physical
C. virtual
Answers
Answer:
virtual
Explanation:
because we cannot touch or sense it
What would be the volume, in liters, of 85.5 grams of carbon monoxide at STP?
Answers
Variables – this experiment tests how the temperature of water affects the time it takes for antacid tablets to dissolve. (they drop an antacid in hot water and one in cold water)
• What is the independent variable? (2 points)
• What is the dependent variable? (2 points)
Answers
Explanation:
You can think of independent and dependent variables in terms of cause and effect: an independent variable is the variable you think is the cause, while a dependent variable is the effect. In an experiment, you manipulate the independent variable and measure the outcome in the dependent variable.
GIVING BRAINLIEST AND THE REST OF MY POINTS!!!!! :D
A scientist made the following table showing the number of eggs laid by two different salmon. Based on this data, which fish has the best chance of their offspring surviving, and what type of adaptation is this?
A) Salmon #1, life cycle adaptation
B) Salmon #1, physical adaptation
C) Salmon #2, life cycle adaptation
D) Salmon #2, behavioral adaptation
Answers
Answer:
C
Explanation:I got it correct on a quiz I did that had this question
Mikala pours a tablespoon of salt into a beaker of water. Diffusion will cause the salt molecules to dissolve in the molecules of water. How could Mikala increase the diffusion rate of the salt molecules?
A. Mikala could remove all sources of light from the beaker.
B. Mikala could slowly pour more water into the beaker.
C. Mikala could decrease the temperature of the solution.
D. Mikala could increase the temperature of the solution.
Answers
Explanation- diffusion rates increase at higher temperatures!
Which of the following best support the claim that the cycling of matter and energy in Earth's interior affects
Earth's surface? Select all correct answers!!!!
A)Tectonic plates move together, apart, and past each other.
B)Lava can be observed rising to Earth's surface in some places.
C)The Earth's crust is much cooler than the Earth's interior.
D)The Earth's inner core is composed mostly of solid iron.
Answers
Answer:
am not sure but I think it c
Answer:
it’s A and B and the last one I still am trying to figure out.
Explanation:
A gas tank contains 2.5 moles of oxygen, 7.0 moles of nitrogen and 0.5 mole of water vapor. The total pressure of the mixture is 852 torr. Calculate the partial pressure of each gas. Show work.
Answers
Answer:
The partial pressure of each gas is:
Oxygen= 213 torrNitrogen= 596.4 torrWater Vapor= 42.6 torrExplanation:
The pressure exerted by a particular gas in a mixture is known as its partial pressure. So, Dalton's law states that the total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert if it were alone:
PT = PA + PB
This relationship is due to the assumption that there are no attractive forces between the gases.
Dalton's partial pressure law can also be expressed in terms of the mole fraction of the gas in the mixture. The mole fraction is a dimensionless quantity that expresses the ratio of the number of moles of a component to the number of moles of all the components present.
The mole fraction of a gas in a gas mixture is given by:
XA = nA / nT
This fraction will always be less than 1.
So in a mixture of two or more gases, the partial pressure of gas A can be expressed as:
PA = XA * PT
In this case, you know:
number of moles of oxygen= 2.5 molesnumber of moles of nitrogen= 7.0 molesnumber of moles of water vapor= 0.5 molesSo, the number of total moles nT is calculated as:
nT= number of moles of oxygen + number of moles of nitrogen +number of moles of water vapor
Then:
nT= 2.5 moles + 7.0 moles + 0.5 moles
nT= 10
So, the mole fraction of the gas in the mixture is:
mole fraction of oxygen = [tex]\frac{2.5 moles}{10 moles}[/tex] = 0.25mole fraction of nitrogen = [tex]\frac{7 moles}{10 moles}[/tex] = 0.7mole fraction of water vapor = [tex]\frac{0.5 moles}{10 moles}[/tex] = 0.05Being the total presurre (PT) equal to 852 torr, then:
Poxygen= 0.25*852 torr= 213 torrPnitrogen= 0.7*852 torr= 596.4 torrPwater vapor= 0.05*852 torr= 42.6 torrThe partial pressure of each gas is:
Oxygen= 213 torrNitrogen= 596.4 torrWater Vapor= 42.6 torr2.00 L of a gas is collected at 25.0°C and 745.0 mmHg. What is the volume at 760.0 mmHg
and 273K?*
Answers
1.7960L
Explanation:
the mass of the gas is constant in both instances
pv/T=constant(according to pv=nRT)
745mmHg*2L/298K=760mmHg*v/273K
v=1.7960L
someone help ,, I'll give brainliest lolll .
Answers
Answer:
the correct answer is c, how easily something catches flames
It’s cold outside and you decide to cook some pasta. As you boil the noodles, the kitchen window begins to fog up. Which processes are at work here?
boiling and freezing
vaporization and condensation
evaporation and thawing
condensation and evaporation
Answers
Answer:
condensation and evaporation
Explanation:
condensation forms when warm humid air contacts cold surface. during cold months.
PLEASE HELP ME EASY
List three household products that should go to a secure landfill site instead of regular sanitary landfill.
Answers
Answer:
plastic, glass, and electronics
Explanation:
those take longer to erode than normal trash.
What element should I do a project on?
Answers
Answer:
Project scope statement?
Explanation:
it's good one just do research on it
what is the name of the part of a cell that allows molecules in in, such as glucose and oxygen?
Answers
Answer:
A plasma membrane is permeable to specific molecules that a cell needs. Transport proteins in the cell membrane allow for selective passage of specific molecules from the external environment. Each transport protein is specific to a certian molecule (indicated by matching colors).
3 – Simple Diffusion Across the Cell (Plasma) Membrane: The structure of the lipid bilayer allows small, uncharged substances such as oxygen and carbon dioxide, and hydrophobic molecules such as lipids, to pass through the cell membrane, down their concentration gradient, by simple diffusion.
Or Cell Membrane
Explanation:
Hope This HElp??
Please MArk Me Brainly!!
generators need sources of energy to produce electricity. which form of energy is a noble where source of energy
A. hydro (water) energy
B. geothermal energy
C. fossil fuel
D. wind energy
Answers
Answer:
B
Explanation:
What is a catalyst and why is it used in chemical reactions?
Answers
Answer:
A catalyst is a substance that can be added to a reaction to speed up the process without being absorbed by it. Catalysts usually work by lowering the activation energy or modifying the mechanism of a reaction. Proteins that act as catalysts in biochemical reactions are known as enzymes.
Explanation:
Sea water contains 2% salt (NaCl) by weight. Given that water has a
density of 1g/mL. Determine the concentration of salt in:
(a) mg/L , (b) ppm.
Answers
Answer:
a) Concentration of salt in mg/L = 2g/100mL
b) concentration in ppm = 20000 ppm
Explanation:
Percentage composition of salt by weight in water = 2%
Density of water = 1 g/mL
100 mL of water will has a mass of 100 g
Mass of salt in 100 g of water = 2% ×100 g = 2 g
Therefore, 2 g of salt is dissolved in 100 mL of solution
Concentration of salt in 100 mL of solution = 2g/100mL
a) Concentration in mg/L
Mass of salt = 2 g = 2000 mg
Volume of solution = 100 mL = 0.1 L
Concentration in mg/L = 2000 mg/0.1 L
Concentration in mg/L = 20000 mg/L
b) Concentration in ppm
1 ppm = 1mg/L
Therefore, concentration in ppm = 20000 ppm
will mark BRAINLYIST
please help
Answers
1.00mol is the correct answer
Earthquakes are common at ocean-continent convergence zones but not ocean-ocean convergence zones. TRUE FALSE Check it
Answers
Answer:
FALSE
Explanation:
The earthquakes are common in both types of convergences is oceanic and continental and ocean to oceanic convergence. As the process of subduction takes places at the oceanic - oceanic boundary and resultant plate slide down other plate leading to recycling of the crust, volcanic eruptions and this leads to the formation of a volcanic arc, trenches, and faults.The orbits of the planets in our solar system are
not
a Elliptical, circular
b Circular, elliptical
C Circular, oval
d None of the above
Answers
Answer:
A
Explanation:
I don't know how to say how I got it.
Answer:
d
Explanation:
the orbits of the planets in our circular elliptical and circular
Но Water Lewis steucture
Answers
what are asking commet it and I might be able to help
Sodium chloride is a ____ substance because the atoms within are arranged in repeating patterns.
work bank
- crystalline
- hydrogen bonds
- hydrophilic
- hydrophobic
- polar molecule
- solvent
Answers
Gases Test
Chemistry
Answers
Answer:
6.64 l is the answer.......
What is the symbol for entropy? S ΔH H ΔS
Answers
Answer:
S
Explanation:
The symbol for entropy is S, and a change in entropy is shown as “delta” S or ΔS. If the entropy of a system increases, ΔS is positive. If the entropy of a system decreases, ΔS is negative.
1. A green rat snake that lives in the grass and a brown rat snake that lives
in the desert is a form of
A. Human genetic modification
B. Selective breeding
C. Natural selection
D. Artificial breeding
Answers
Answer:
It is an example of natural selection (option c)
Natural selection is demonstrated by a green rat snake living within that grass as well as a brown rat snake living throughout the desert.
Natural selection:The process throughout which communities of sentient creatures adapt but instead transform is known as natural selection. Persons within a demographic are inherently varied, which means they are all unique under certain manner.
This variance indicates that certain people have qualities that are more adapted to their surroundings over others.
Thus "Option C" is correct.
Find out more information about Natural selection here:
https://brainly.com/question/14485249
why is it necessary to specify temperature when giving Ka value
Answers
Answer:
Because the equilibrium constant is only at constant at temperature. Changing the temperature changes the Ka.
Matching
Enter the letter of the box whose contents best match the description.
8
8
8
a
b
с
e
f
v a mixture of molecules
atoms of a pure elementa metal
molecules of an element
va solid compound
a mixture of elements
a. box a
b. box e
c. box b
d. box f
e. box d
f. box c
QUESTION 10
Answers
Answer:
a mixture of molecules - Box f
atoms of a pure elementa metal - Box D
a solid compound - Box C
a mixture of elements - Box A
Explanation:
Box a has mixture of elements which forms a solid like shape but there are different elements present in the box. The box f has mixture of molecules in which many atoms are combined together. Box c has solid compound with single element.