Answers
Answer:
Option a is a solution acidic ([OH⁻] = 7.0x10⁻⁹ M).
Explanation:
To know if a solution is acidic we need to calculate the pH and it must be lower than 7. A value of pH equal to 7 is a neutral solution and a solution with a pH value higher than 7 is a basic solution.
a. For the [OH⁻] = 7.0x10⁻⁹ M we have:
[tex] pOH = -log[OH^{-}] = -log(7.0 \cdot 10^{-9}) = 8.15 [/tex]
Now, the pH is:
[tex] pH + pOH = 14 [/tex]
[tex] pH = 14 - pOH = 14 - 8.15 = 5.85 [/tex]
This solution is acidic (pH < 7)
b. [H₃O⁺] = 8.5x10⁻⁸ M
[tex] pH = -log(8.5 \cdot 10^{-8}) = 7.07 [/tex]
This is not an acidic solution. Is a neutral one (pH around to 7).
c. [OH⁻] = 2.5x10⁻⁶ M
[tex] pOH = -log[OH^{-}] = -log(2.5 \cdot 10^{-6}) = 5.60 [/tex]
Then, the pH is:
[tex]pH = 14 - pOH = 14 - 5.60 = 8.40[/tex]
Hence, this is not an acidic solution. It is basic (pH > 7).
Therefore, option a is a solution acidic ([OH⁻] = 7.0x10⁻⁹ M).
I hope it helps you!
Related Questions
Mr. Green gave his students a set of items.
They had a toothpick, pencil, paper clip, safety pin, nail, and dime. He also gave them a magnet. He told them to predict which items are magnetic.
How can they test their predictions?
A.
weigh each of the items
B.
see which items stick to the pencil
C.
measure each of the items
D.
see which items stick to the magnet
Answers
Answer:
D. see which items stick to the magnet
Explanation:
To predict which items are magnetic, the students will have to test whether or not each item is attracted to the magnet. Only objects that are magnetic stick to a magnet, so all of the items that stick to the magnet should be magnetic.
Hopefully that's helpful! :)
3. Type: MT
Match the term to the correct definition
1. Homogeneous mixture
a. same throughout
2. Heterogeneous mixture
b. different throughout
Answers
Homogeneous mixture - same throughout
Heterogeneous mixture - different throughout
Answer: Homogeneous Mixture : B(different throughout)
Heterogeneous Mixture : A(same throughout)
calculate the speed of a train that travels 540 km in 9 hours
Answers
Answer:
s=d/t. d=540 t=9h
540÷90=6 km/h
A chemist dilutes a 1. 0 mL sample of 2. 0 M KNO3 by adding water to it. If the concentration of the solution that is obtained is 0. 0080 M, what is its volume? Use M subscript i V subscript i equals M subscript f V subscript f. 125 mL 250 mL 500 mL 2,000 mL.
Answers
Answer:
We know the initial volume of the potassium nitrate solution is 1.0 mL and the initial concentration is 2.0 M, we also know that an unknown volume of water was added to the solution, which diluted our concentration down to a final value of 0.008 M. We are trying to find the final volume.
Here we can use this formula since the initial and final solutions are proportional. Before that let's define our variables.
[tex]M_1 = 2.0 M\\V_1 = \frac{1.0 mL}{1000} = 0.001 L\\M_2 = 0.008 M\\V_2 = \ ?[/tex]
[tex]M_{1}V_{1} =M_2 V_2\\[/tex]
[tex](2.0)(0.001) = (0.008)V_2\\\\\frac{(2.0)(0.001)}{0.008} = V_2\\\\V_2 = 0.25 L \ or \ (0.25 \ * \ 1000) = 250 \ mL[/tex]
Therefore you would have 0.25 L or 250 mL of your final solution.
Note the mass of copper(1) oxide formula unit 143.091 what is the mass of 8.250 moles of Cu2O
Answers
Answer:
The mass of 8.250 moles of Cu2O is 1180.5g
Explanation:
HOW TO CALCULATE MASS OF A SUBSTANCE:
The mass of a substance can be calculated by multiplying the number of moles in the substance by its molar mass as follows:Mass (g) = no. of moles (mol) × molar mass (g/mol)
Molar mass of copper (I) oxide (Cu2O) = 63.5(2) + 16 = 143.09 g/molMass of Cu2O = 8.250 mol × 143.09 g/mol
Mass of Cu2O = 1180.5 g
Therefore, the mass of 8.250 moles of Cu2O is 1180.5 g.
The bacteria are known to be prokaryotes. Prokaryote means
A
organisms whose cells have no nucleus
B
organisms who are made of many cells
C
organisms who make their own food
D
organisms whose cells have a nucleus
Answers
Answer:
prokaryote, also spelled procaryote, any organism that lacks a distinct nucleus and other organelles due to the absence of internal membranes. ... Bacteria are among the best-known prokaryotic organisms. The lack of internal membranes in prokaryotes distinguishes them from eukaryotes.
Explanation:
What foods have been allowed or banned in which countries? Why?
please please help me
Answers
Marmite was banned in Denmark in 2004 because of a law that resourced food products that were fortified with vitamins. Marmite had yeast extract. Technically, Denmark hasn’t banned Marmite, it’s more the additional vitamins minerals and such.
Haggis was banned in the US dba sue it contained sheep lung, which violates federal safety regulations.
McCain Brand French Fries have been banned in several countries, such as the UK and Australia, because it has a asthma including chemical called azodicarbonamide
Why are metals sometimes added to gold?
to make it softer and more malleable
to improve the value of gold
to raise its melting point
to make gold stronger and more durable
Answers
A chemist heats a gas within a sealed, rigid container. Which statement describes the changes that occur in the gas? (1 point)
-The gas particles move slower and hit the sides of the container with less force, consequently, the pressure
increases
-The gas particles move slower and hit the sides of the container with less force, consequently, the pressure decreases
-The gas particles move faster and hit the sides of the container with more force, consequently, the pressure
increases
-The gas particles move faster and hit the sides of the container with more force, consequently, the pressure
decreases
Answers
When a gas is heated in a sealed container, the gas particles move faster and hit the sides of the container with more force leading to an increase in the pressure of the gas.
An increase in the temperature of a gas increases the collision rate of the molecules of the gas according to the kinetic theory.
With increased kinetic energy, the molecules of the gases collide more frequently with each other and the walls of the container.
The collision creates an increase in the magnitude of pressure inside the container.
More on the kinetic theory of gases can be found here: https://brainly.com/question/15354399?referrer=searchResults
Answer:
C
Explanation:
When a gas is heated in a sealed container, the gas particles move faster and hit the sides of the container with more force leading to an increase in the pressure of the gas.
• If the distance between Earth and the Moon decreased by half, how would it affect the
weight of a person on Earth?
Answers
Answer:
look at the explanation
Explanation:
Tides would be much higher also A lunar month would be about 10 days rather than 29 days, so the phases of the moon would go much quicker.
How does a paper bag wrapped around a hot water bottle create convection?
Answers
Heat is a form of energy. You need energy to heat something up: for example, a cup of tea. To make your tea you probably use energy from electricity or gas. However, once your tea is hot, it won't stay hot forever. Just leave the cup of tea out on the table for a while, and you already know that it will become cooler the longer you wait. This is due to a phenomenon called heat transfer, which is the flow of energy in the form of heat. If two objects have different temperatures, heat automatically flows from one object to the other once they are in contact. The heat energy is transferred from the hotter to the colder object. In the case of the tea, the heat of the liquid is transferred to its surrounding air, which is usually colder than the tea. Once both objects reach the same temperature, the heat transfer will stop. Heat transfer via movement of fluids (liquids or gases) is called convection.
Want to keep warm this winter? Try this "cool" activity and find out what types of insulation work best--and why. Credit: George Retseck
ADVERTISEMENT
Key concepts
Physics
Heat transfer
Insulation
Material science
Introduction
What do you do when it gets very cold in winter? You probably turn your heater on, put on an extra layer of clothes or cuddle under a warm blanket. But have you ever thought about why a jacket helps you stay warm? Why are our clothes made from fabrics and not foils? Find out the answers in this activity; your results might even help you find the best way to stay warm in the cold!
Background
Heat is a form of energy. You need energy to heat something up: for example, a cup of tea. To make your tea you probably use energy from electricity or gas. However, once your tea is hot, it won't stay hot forever. Just leave the cup of tea out on the table for a while, and you already know that it will become cooler the longer you wait. This is due to a phenomenon called heat transfer, which is the flow of energy in the form of heat. If two objects have different temperatures, heat automatically flows from one object to the other once they are in contact. The heat energy is transferred from the hotter to the colder object. In the case of the tea, the heat of the liquid is transferred to its surrounding air, which is usually colder than the tea. Once both objects reach the same temperature, the heat transfer will stop. Heat transfer via movement of fluids (liquids or gases) is called convection.
Another type of heat transfer is conduction, in which energy moves through a substance (usually a solid) from one particle to another (unlike in convection where it’s the heated matter itself that moves). A pot handle getting hot would be an example of conduction.
The pH scale is used to tell if a substance
is an acid or base. Substances with a pH
of 7 are neutral. An acid is anything
below 7 and a base is anything above
7.What would a household cleaner with a
pH of 10 be considered on the pH scale?
Answers
Answer:
Explanation:
pH > 7 as 10 is more than 7
The cleaner is very corrosive.
It is a moderately basic. If it was 12 that would make it much more basic (100 times more basic).
Which animal is found in the desert?
monkeys
parrots
buffalo
meerkats
Answers
Answer:
meerkats
Explanation:
A substance that takes the shape and volume of its container is in this phase is called a liquid
Answers
Answer:
liquid matter
Explanation:
using the two ways you have learned about between temperature, pressure and volume, what are two ways you could increase the gas pressure of a system.
Answers
Answer:
I don't know do you know tell me please
A force is a push or a pull under the right circumstances anything can exert a force push a notebook or some other object so that it slides across a table or desktop what force causes the notebook to start moving what force causes the notebook to stop moving?
Answers
Answer:
the force that you applied caused the notebook to move.the force applied on the notebook by the table causes it to stop moving. this is because after sometime the book uses up the force and later the force you applied is less than that of the force by the table.
Hellpppppppppppppppppppppp
Answers
Answer:
SnH4
Explanation:
Because the melting point of SnH4 is higher than CH4
What is the volume in mL of 1 Kg of gold? The density of gold is 19.3 g/mL.
Answers
Answer:
Volume occupied is approx.
38 ⋅ ML
Explanation:
Density ρ = Mass Volume And thus Volume = Mass ρ = 1.592 ⋅ l b × 454 ⋅ g ⋅ l b − 1 19.3 ⋅ g ⋅ m L − 1 = ? ? ⋅ m L
How to get your crush to like you back
Answers
i’m just going to say this…
if people stop talking to you, or seeing you it’s for a reason. things don’t happen on accident, so if your crush stopped liking you then it was for a reason wether you realize it or not.
hope this helps!
Which of the following could be classified as producing a physical change?
A. Burning a candle
B. Leaving a bicycle outside to rust
C. Bending sheet metal
D. Toasting a slice of bread
Answers
Answer:
C. Bending sheet metal.
Explanation:
The metal is still intact. No change in chemical bonds have occurred.
Burning a candle is converting wax into heat, CO2 and carbon soot.
A rusting bicycle is converting goof iron, Fe, into iron oxide (rust, Fe2O3)
Toasting bread is more difficult to define. If the bread is just warmed, then it is physical. If it is toasted (browned/burned), then a few surface molecules have been converted into tasty carcinogens, my favorite poison.
Elements are usually dull, brittle and do not conduct electricity are know as_____.
Points: 46
Answers
Answer:
nonmetals. it's one of them
during hybridization ______.
A) nature selects which organisms will survive and reproduce.
B) the nucleus of a cell is removed.
C) two organisms with desired traits are bred.
D) a single beneficial trait is bred into a species.
Answers
Answer:
option C two organisms with desired traits are bred
When you take a hot shower, the
a
shower curtain sometimes moves
into the shower towards you. Why
does this happen?
Answers
With hot water comes hot steam, it fills the shower area with steam which raises the air temperature and the air then rises out of the shower
What is the molarity of a 75.0 mL solution that contains 0.225 g of
potassium nitrate?
Answers
Answer:
M=0.0297M
Explanation:
we know that molarity equals number of mole of solute over the volume of solution.
M=n/V but n=m/M
n=0.225g÷101g/mol =0.00223mol
M=0.00223mol/0.075l
M=0.0297M
Answer:
0.0297M
Explanation:
We will use the formula M= moles of solute/lites of solution.
First we need to figure out the Moles of the solute, to get this we first need the molar mass of KNO3 (potassimum nitrate).
The Molar Mass of potassimum nitrate is 101.103 g/mol
K - 1 x 39.09
N - 1 x 14.006
O - 3 x 15.999
KNO3 - 101.103 g/mol
Now we get the moles of the solute by doing.
0225g/ 101.103g/mol = 0.00223 mol
Put the answer into the orginal equation to get 0.00223mol / 0.045 L
Which equals to 0.0297M. This is also the correct amount of significant figures.
How do you break down an element?
Answers
Answer:
elements cannot be break downPlease help me with this three questions
Answers
Answer:
1. A. Thyroid Gland Function
B. detecting Blood Clots
C. Treating Cancer
2. An example would be how many are used as tracers for diagnostic purposes
3. Beneficial because it gives us ways to eleminate pests, by the sterile insect technique
Number three is kinda iffy a bit difficult to explain it may be explained better in your book.
Elements that are usually shiny and good conductors of heat and electricity are known as_______.
Points: 70
Answers
Is it unbalanced or balanced if hydrogen reacts to iodine?
Answers
Answer:
unbalanced
Explanation:
because it is REACTing.
What type of mixture is throughly mixing powdered lemonade with water
Answers
Answer:
I believe it would be a solution I could be wrong tho
Explanation:
Answer:
a solution
Homogeneous mixtures (solutions)
Explanation:
Lemonade is a special type of mixture called a solution.
...................................................................................................................................................
What type of mixture is made by thoroughly mixing powdered lemonade with water?
Homogeneous mixtures (solutions)
Mixtures with substances dissolved evenly into one another, like pink lemonade powder dissolved in water, are called homogeneous mixtures, or solutions.
For the balanced equation shown below, how many grams of CO2 will be
produced from 74.23 grams of CO? CO + Fe3O4 → 3FeO + CO2
Answers
Answer:
116.64 g
Explanation:
74.23÷14 This is # of moles .
# of moles for co = 5.302
Then mass of co2 = 116.64
