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!
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
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! :)
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
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.
How to get your crush to like you back
Elements are usually dull, brittle and do not conduct electricity are know as_____.
Points: 46
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.
Answer:
option C two organisms with desired traits are bred
Elements that are usually shiny and good conductors of heat and electricity are known as_______.
Points: 70
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
calculate the speed of a train that travels 540 km in 9 hours
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.
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.
Which animal is found in the desert?
monkeys
parrots
buffalo
meerkats
Answer:
meerkats
Explanation:
What type of mixture is throughly mixing powdered lemonade with water
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.
Is it unbalanced or balanced if hydrogen reacts to iodine?
Answer:
unbalanced
Explanation:
because it is REACTing.
What foods have been allowed or banned in which countries? Why?
please please help me
How does a paper bag wrapped around a hot water bottle create convection?
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?
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).
• If the distance between Earth and the Moon decreased by half, how would it affect the
weight of a person on Earth?
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.
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
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:
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
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.
How do you break down an element?
Answer:
elements cannot be break downA 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?
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.
What is the volume in mL of 1 Kg of gold? The density of gold is 19.3 g/mL.
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
What is the molarity of a 75.0 mL solution that contains 0.225 g of
potassium nitrate?
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.
Hellpppppppppppppppppppppp
Answer:
SnH4
Explanation:
Because the melting point of SnH4 is higher than CH4
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.
Answer:
I don't know do you know tell me please
Please help me with this three questions
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.
For the balanced equation shown below, how many grams of CO2 will be
produced from 74.23 grams of CO? CO + Fe3O4 → 3FeO + CO2
Answer:
116.64 g
Explanation:
74.23÷14 This is # of moles .
# of moles for co = 5.302
Then mass of co2 = 116.64
When you take a hot shower, the
a
shower curtain sometimes moves
into the shower towards you. Why
does this happen?
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
3. Type: MT
Match the term to the correct definition
1. Homogeneous mixture
a. same throughout
2. Heterogeneous mixture
b. different throughout
Homogeneous mixture - same throughout
Heterogeneous mixture - different throughout
Answer: Homogeneous Mixture : B(different throughout)
Heterogeneous Mixture : A(same throughout)
Note the mass of copper(1) oxide formula unit 143.091 what is the mass of 8.250 moles of Cu2O
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.
A substance that takes the shape and volume of its container is in this phase is called a liquid
Answer:
liquid matter
Explanation: