Which solution is the least concentrated?
O 2 moles of solute dissolved in 4 liters of solution
Use a scientific calculator to calculate [H+] for the following pH values:
7 (a neutral solution)
5.6 (unpolluted rainwater)
3.7 (first acid rain sample in North America)
How many times higher is the concentration of H+ in the Hubbard Brook sample than in unpolluted rainwater?
Answer:
pH = 7 ⇒ [H⁺] = 1.0x10⁻⁷ M
pH = 5.6 ⇒ [H⁺] = 2.5x10⁻⁶ M
pH = 3.7 ⇒ [H⁺] = 2.0x10⁻⁴ M
H⁺ concentration in the Hubbard Brook sample is 80 times higher than in unpolluted rainwater.
Explanation:
To answer this problem we need to keep in mind the definition of pH:
pH = -log[H⁺]Meaning that after isolating [H⁺] we're left with:
[H⁺] = [tex]10^{-pH}[/tex]Now we proceed to calculate [H⁺] for the given pHs:
pH = 7 ⇒ [H⁺] = [tex]10^{-7}[/tex] = 1.0x10⁻⁷ MpH = 5.6 ⇒ [H⁺] = [tex]10^{-5.6}[/tex] = 2.5x10⁻⁶ MpH = 3.7 ⇒ [H⁺] = [tex]10^{-3.7}[/tex] = 2.0x10⁻⁴ MFinally we calculate how many times higher is [H⁺] when pH = 3.7 than when pH = 5.6.
2.0x10⁻⁴ / 2.5x10⁻⁶ = 80Answer:
1. 7 (a neutral solution)
Answer: 10-7= 0.0000001 moles per liter
2. 5.6 (unpolluted rainwater)
Answer: 10-5.6 = 0.0000025 moles per liter
3. 3.7 (first acid rain sample in North America)
Answer: 10-3.7 = 0.00020 moles per liter
The concentration of H+ in the Hubbard Brook sample is 0.00020/0.0000025, which is 80 times higher than the H+ concentration in unpolluted rainwater.
Explanation: -
Revise this statement to make it true:
Running water makes rock edges very sharp and pointy.
NEED HELP NOW PLEASE!! WHOEVER ANSWERS FIRST GETS BRAINIEST!!! No links or I’m reporting your answer.
Answer:
Running water makes rock edges very dull because of erosion.
Explanation:
hope this helps ^_^
Which element would be the most suitable to make a spoon that will melt in
your hot drinks?
A) aluminium
melting point: 660°C
boiling point: 2470°C
B) argon
melting point: -189°C
boiling point:-186°C
C) bromine
melting point: -7°C
boiling point: 59°C
D) gallium
melting point: 30°C
boiling point: 2400°C
E) lithium
melting point: 180°C
boiling point: 1330°C
F)mercury
melting point: -39°C
boiling point:357°C
Answer:
it's A) or E)
others are not suitable cuz their melting point is weak.
Answer:
Gallium
Explanation:
Because the melting point is low and the drinks are usually around 60-70 degrees Celsius so it wil melt
Pleseee help me pretty please ✨
Answer:
6 N.
Every thing has equal and opposite reaction.
Answer:
The answer is C I believe, I do not know for sure but I think that is the answer..
I'm sorry if I'm wrong.
Explanation:
Which statement correctly describes the relationship between air temperature and air pressure?
-Warm air rises, creating an area of low pressure.
-Cool air sinks, creating an area of low pressure.
-Warm air sinks, creating an area of low pressure.
-Cool air rises, creating an area of low pressure.
Answer:
-Warm air sinks, creating an area of low pressure.
Explanation:
Heat will weigh more, than cool air!
Which of the nine substances are made of three elements?
Answer: You are made of mostly 6 elements: Oxygen, Carbon, Hydrogen, Nitrogen, Calcium, and Phosphorus. Some of these elements combine to form compounds in your body.
Explanation:
Identifying Cell Structures
Which structures are found in plant colls, but not in animal cells? Check all that apply
)
coll wall
coll membrane
chloroplasts
O lysosomes
ribosomes
vacuoles
Answer:
cell wall and chloroplasts
Explanation:
18.
react to cause chemical reactions
Protons
Neutrons
Electrons
Pls 50 points right answer gets brainliest
Explain the meaning of thermal energy transfer and give specific examples of conduction, convection, and radiation.
Answer:
thermal energy: the part of total internal energy that can be transferred (a portion of the kinetic energy)
heat is the thermal energy that flows from one substance to another due to a temperature difference.
Thermal energy is measured in temperature change.
Thermal energy transfer stops when thermal equilibrium is achieved (Both substances at the same temperature).
conduction: Transfer of thermal energy through a solid object like heat transferring up a metal spoon from a hot cup of coffee.
convection: the transfer of thermal energy due to the movement of a liquid or gas caused by differences in temperature. Only in a fluid (liquid or gas). Breezes, ocean currents.
radiation: Transfer energy with or without matter. Warming from the Sun, microwave oven.
Answer:
Conduction is the transfer of thermal energy through direct contact. Convection is the transfer of thermal energy through the movement of a liquid or gas. Radiation is the transfer of thermal energy through thermal emission. Hope this helps!
Explanation:
Present in a state where it molecules are far apart during a change of state it's molecules slow down which change of state has most likely taken place from a gas to a liquid from a liquid to a gas from a solid to a liquid from a gas to a plasma
Answer:
The change of state that has occurred is from a gas to a liquid
Note: The question is incomplete. The complete question is given blow.
H₂O is initially present in a state where its molecules are far apart. During a change of state, its molecules slow down. Which change of state has most likely taken place?
from a gas to a liquid
from a liquid to a gas
from a solid to a liquid
from a gas to a plasma
Explanation:
Water can exists in three states: as gaseous water vapor, as liquid water, and as solid ice. Each of these states of water can be interconverted from one to another by the addition or removal of heat in a process known as change of state.
Liquid water can be converted to solid ice by the removal of heat, while solid ice ice can be converted to liquid water by the addition of heat. Also, liquid water can be converted to water vapor by the addition of heat, while water vapor can be converted to liquid water by the removal of heat.
Of the three states of water, the one in which the molecules are farthest apart is in the gaseous state. The molecules have high kinetic energy and move randomly while colliding with one another. When a heat is removed from these highly energetic molecules, the molecules slow down and lose some of their kinetic energy and a change of occurs from gaseous to liquid state.
Therefore, the change of state that occurred as described, is from gas to liquid.
when a rotting log was turned over, pill bugs, termites , ants , fungi , and earthworms were living there. the termites represent ____ in its
a. an environment
b. a population
c. a niche
d. an abiotic factor
What is the correct formula for the missing product from the equation below:
Na2CO3(aq)
+
CaCl2 (aq)
> NaCl +
Answer:
CaCO3 (s)
Explanation:
This equation is a double replacement equation, which means that since Na and Cl and paired, Ca and CO3 will be paired.
Then, you look at the charge of each element and balance
Ca has a 2+ charge
CO3 has a 2- charge
The 2+ charge and the 2- charge will cancel so there is no need for a subscript or to balance the equation
The complete equation will be Na2CO3 (aq) + CaCl2(aq) -> NaCl (aq) + CaCO3 (s)
I hope this helps and have a great day!
Give one example of
a) Homogeneous mixture of two elements
Answer:
honey
Coffee
blood
Explanation:
These components are uniformly distrubuted and these cannot be seperated unlike heterogeneous
When naming an acid, which of the following is true?
chlorite changes to chloric acid
chlorate changes to chloric acid
none of these is true
chlorate changes to chlorous acid
Answer:
chlorate changes to chlorous acid
how many mols are in 100.g of Fe?
Answer:
1.79 moles
Explanation:
1.79 moles
1.79 moles
1.79 moles
1.79 moles
Answer:1.79 moles
1.79 moles are there in 100g of iron.
Explanation:
thats the answer for it
Which feature separates watershed
Answer:
Ridges.
Explanation:
Watersheds are separated from one another by ridges. Ridges are elevated boundaries that divide watersheds.
31. Solve this Gibbs' Free Energy Equation:
For a reaction at 200 K, the Delta H has a value of 250 kJ and the Delta S has a value of 0.100 kJ. 1s
the reaction spontaneous or not spontaneous?
Answer:The standard Gibbs energy change at 300K for the reaction 2A⇔B+C is 2494.
Explanation:
ΔG = free energy at any moment.
ΔGo = standard-state free energy.
R is the ideal gas constant = 8.314 J/mol-K.
T is the absolute temperature (Kelvin)
lnQ is natural logarithm of the reaction quotient
Why is there a hole in the ozone layer? What do you think the consequences of that hole are?
Answer:
There is a ozone layer because of the special atomphere and chemical conditions that takes place there. I think the consequences of that home area is the very low winter temperatures.
Answer:
There is a hole in the ozone layer because of the pollution on earth. Because of that the UV rays are easily entering the earth through that portion. The consequences of this can be cancers, global warming and disastrous storms.
plz mark as brainliest
A 25.00 mL sample of the ammonia solution
was accurately diluted to 250.0 mL. A 25.00mL
aliquot of the diluted ammonia solution was
placed in a conical flask. Indicator was then added
and the solution was titrated with 0.208 molL-1
hydrochloric acid. The indicator changed colour
permanently when 19.64 mL of the acid had been
added. Calculate the concentration of ammonia in
the original solution.
Answer:
1.634 molL-1
Explanation:
The mol ration between NH3 and HCl is 1 : 1
Using Ca Va / Cb Vb = Na / Nb where a = acid and b = base
Na = 1
Nb = 1
Ca = 0.208 molL-1
Cb = ?
Va = 19.64 mL
Vb = 25.00mL
Solving for Cb
Cb = Ca Va / Vb
Cb = 0.208 * 19.64 / 25.0
Cb = 0.1634 molL-1 (Concentration of diluted ammonia solution)
Using the dilution equation;
C1V1 = C2V2
Initial Concentration, C1 = ?
Initial Volume, V1 = 25.00 mL
Final Volume, V2 = 250 mL
Final Concentration, C2 = 0.1634 molL-1
Solving for C1;
C1 = C2 * V2 / V1
C1 = 0.1634 * 250 / 25.00
C1 = 1.634 molL-1
Did anyone do this worksheet (science)
The diffusion of matter and energy in a liquid is slower than diffusion in a gas
True
O False
If an electron has an acceleration of 2.33 × 102 m/sec2, what is this value in units of m/min2?
Answer:
The electron has an acceleration of 838800 [tex]\frac{m}{min^{2} }[/tex]
Explanation:
An electron has an acceleration of 2.33*10² [tex]\frac{m}{sec^{2} }[/tex]
To be able to express in units [tex]\frac{m}{min^{2} }[/tex], you must carry out the conversion taking into account that 1 [tex]\frac{m}{sec^{2} }[/tex]= 3600 [tex]\frac{m}{min^{2} }[/tex]. Then you can apply the following rule of three: if 1 [tex]\frac{m}{sec^{2} }[/tex] equals 3600 [tex]\frac{m}{min^{2} }[/tex], 2.33 * 10² [tex]\frac{m}{sec^{2} }[/tex] equals how much [tex]\frac{m}{min^{2} }[/tex]?
[tex]\frac{m}{min^{2} }=\frac{2.33*10^{2} \frac{m}{sec^{2} }*3600\frac{m}{min^{2} }}{1\frac{m}{sec^{2} }}[/tex]
[tex]\frac{m}{min^{2} }=838800[/tex]
The electron has an acceleration of 838800 [tex]\frac{m}{min^{2} }[/tex]
I went for a walk the other day. I went four blocks east, then seven blocks south, then one block west and finally
eight blocks north
a.What distance did I travel?
b. What's my displacement?
Answer:
a) distance is 4+7+1+8=20 blocks
b) displacement is 10 blocks
Explanation:
find displacement: x and y
x axis displacement = 4-1 = 3 blocks
y axis displacement = -7+8= 1 block
displacement = the square root of 3^2 + 1^2
= 9+1 = 10 blocks.
You can find the angle of displacement with respect to the initial position using trig identities, if you wish.
Which of the following pairs of elements will combine to produce a covalent bond?
1-Hydrogen and chlorine
2-Magnesium and oxygen
3-Lithium and bromine
Answer:
Hydrogen and Chlorine
ie HCL
The pairs of chemical elements that will combine to produce a covalent bond is: 1. Hydrogen and chlorine.
In Chemistry, the three (3) main types of chemical bonds include:
Ionic bonds: Lithium and bromineHydrogen bonds: Hydrogen and oxygen.Covalent bonds: Hydrogen and chlorine.A covalent bond can be defined as a type of bond that typically involves the sharing of electrons between the atoms of a chemical element.
For example, the type of bond that is produced (formed) between hydrogen atoms and a chlorine atom is a covalent bond.
The hydrogen atom shares it single electron with a chlorine atom that is having seven (7) valence electrons to produce an inert gas such as hydrochloric acid (HCL).
In conclusion, the pairs of chemical elements that will combine to produce a covalent bond is hydrogen and chlorine.
Read more: https://brainly.com/question/24212500
how many moles is 130g of cocl2
Answer:
1.3142 mol CoCl2
Explanation:
Well, to answer this we need to find out how many grams are in a single mole of CoCl2. Two find that we need to get the molar mass of CoCl2
Co = 28.0101 g Co per mole
Cl = 35.453 * g Cl per mole
28.0101 + 2 * 35.453 = 98.9161 g CoCl2 per mole
Now, we divide:
130/98.9161 = 1.3142 mol CoCl2
There are 1.31 moles in 130grams of cobalt chloride (CoCl2). Details about how to convert mass to moles can be found below.
How to calculate number of moles?The number of moles of a substance can be calculated by dividing the mass of the substance by its molar mass.
According to this question, there are 130g of CoCl2.
molar mass of CoCl2 = 28 + 35.5(2) = 99g/mol
moles = 130g ÷ 99g/mol
moles = 1.31 moles
Therefore, there are 1.31 moles in 130grams of cobalt chloride (CoCl2).
Learn more about number of moles at: https://brainly.com/question/14919968
Which of these statements describes a physical property of hydrogen? Group of answer choices it is found in acids. it is less dense than oxygen gas. it reacts with oxygen to form water. it is highly flammable.
Answer:
it is less dense than oxygen gas.
Explanation:
Hydrogen is the simplest chemical element that exists. The symbol for the chemical element Hydrogen is "H" and it is a colourless, tasteless, odorless, and highly flammable gas.
Hydrogen is a chemical element found in group (1) of the periodic table and as such it has one (1) electrons in its outermost shell. Therefore, Hydrogen has an atomic number of one (1) and a single valence electrons because it has only one proton and one electron in its nucleus.
In Chemistry, the properties of a chemical element that can be observed and measured without changing its chemical nature is known as a physical property. It includes density, color, freezing point, opacity, smell, melting point, viscosity, etc.
Hence, the statement which describes a physical property of hydrogen is that it is less dense (density) than oxygen gas.
most of the earth's landmasses is covered by a mixture of bits of rock and bit of once~living part of plants or animal. this material is called
and its not fossil
A 500-gram block of solid cheese is melted in a pot. Which is most likely be the mass of the cheese after it is melted?
pleaseeeeeeeeee answer
Answer:
due to the law of conservation of mass, the mass would stay the same.
1 mole of any gas is equivalent to?
Answer:
22.4 L at standard temperature and pressure.
before you retire in the evening, you sit down for a snack of milk and cookies. when you waken in the morning, you discover a carton of sour milk on the counter. knowing that milk sours if left in the refrigerator too long, has the reaction rate increased or decreased for the carton of milk on the counter? what has happened to its reaction time
Answer:
Increased
Explanation:
We know that the higher the temperature the higher the rate of reaction. This implies that as the temperature is increased, a reaction tends to proceed faster.
This follows from the collision theory, the higher the temperature, the higher the energy of the reacting particles hence they collide with each other faster and more effectively.
Thus the rate of reaction( or reaction time) for the carton of milk on the counter was increased.