Answer:
and now you have a nail in your wood :)
How many grams of sodium hypochlorite (NaClO)is required to make abuffer with pH= 7.35 if you had 500 mL of a 0.1M solution of hypochlorous acid with pKa=7.54.(Assume the addition of NaClO does not change the volume.)
Answer:
2.4g of NaClO must be added
Explanation:
To find the pH of a buffer we must use H-H equation:
pH = pKa + log [A⁻] / [HA]
Where pH is the pH of the buffer, 7.35
pKa of the HClO buffer is 7.54
[A⁻] could be taken as moles of NaClO
And [HA] moles of the weak acid: 500mL = 0.500L * (0.1mol/L) = 0.05 moles
Replacing:
pH = pKa + log [A⁻] / [HA]
7.35 = 7.54 + log [A⁻] / [0.05moles]
0.6457 = [A⁻] / [0.05moles]
0.03228 moles = Moles of NaClO we need to make the pH = 7.35 buffer.
To convert these moles to grams we use the molar mass of NaClO (74.44g/mol):
0.03228 moles * (74.44g/mol) =
2.4g of NaClO must be added
Violet light has a wavelength of 4.50 x 10-12 m. What is the frequency?*
3 points
1.5 x10^20 1/s
0.0135 1/s
6.77x10^19 1/5
3x10^8 1/s
Green light has a frequency of 6.73 x 1014 1/s. What is the wavelength?*
3 points
2.24x10^6 m
4.46x10^-7 m
2.02 x 10^23 m.
4.95 x 10^-24 m
3 points
What is the energy (Joules) of violet light with a frequency = 3.43 x 10^14
1/s? *
4.54x10^-19 J
1.99x10^-25 J
1.93 x 10^-48 J
2.27 x 10^-19 J
Answer:
Frequency = 6.67x10¹⁹ s⁻¹
Wavelength = 4.46x10⁻⁷m
e = 2.27x10⁻¹⁹J
Explanation:
To convert frequency to wavelength and vice versa we use the equation:
Wavelength = Speed of light / Frequency
Speed ligth is 3x10⁸m/s
For a wavelength of 4.50x10⁻¹²m:
4.50x10⁻¹²m = 3x10⁸m/s / Frequency
Frequency = 3x10⁸m/s / 4.5x10⁻¹²m
Frequency = 6.67x10¹⁹ s⁻¹For a frequency of 6.73x10¹⁴s⁻¹:
Wavelength = 3x10⁸m/s / 6.73x10¹⁴s⁻¹
Wavelength = 4.46x10⁻⁷mAnd energy, e, from frequency, is obtained as follows:
e = h ₓ frequency
Where h is Planck's constant, 6.626x10⁻³⁴J*s
e = 6.626x10⁻³⁴J*s*3.43x10¹⁴s⁻¹
e = 2.27x10⁻¹⁹JDoes the Bohr model work for atoms other than hydrogen?
Answer:
The "Bohr Model", works only for hydrogen because it considers only the "interactions" between one electron and the nucleus.
Explanation:
$*
Consider the reaction of 30.0 mL of 0.235 M BaI₂ with 20.0 mL of 0.315 M Na₃PO₄.
Which of the following compounds would be the precipitate that forms?
a) Bal2
b) Na3PO4
c) Ba3(PO4)2
d)Nal
Answer:
C
Explanation:
Because sodium is basically always soluble with any compound, it is between a and c. a is part of the reactant so it cant be A. So C.
The statement, that describes the compounds would be the precipitate that forms in the reaction is "Ba3(PO4)2"
What is precipitate?Precipitate is a solid generated by a change in a solution, usually due to a chemical reaction or a change in temperature that reduces a solid's solubility.
What is compound?The combination of more than one element will be identified ad compound.
When cations and anions in aqueous solution combine to create an insoluble ionic solid called a precipitate, double displacement reactions occur, resulting in the formation of a solid form residue. Except for salts of Group 1 metals and ammonium, salts of phosphates and carbonates ions are insoluble, according to the solubility flow chart. The production of a solid white precipitate is used to demonstrate the insoluble nature of barium phosphate.
Hence the correct option is c.
Learn more about precipitate here,
https://brainly.com/question/18109776
#SPJ2
Which of the following is true?
A) The closer an electron is to the nucleus, the higher its energy level.
B) The closer an electron is to the nucleus, the lower its energy level.
C) The closer an electron is to the nucleus, the more its energy level fluctuates.
D) There is no relationship between proximity to the nucleus and the energy level of an electron
Answer:
B) The closer an electron is to the nucleus the lower it's energy level.
Explanation:
This is because the attractive force for electrons to the nucleus is stronger. Thus, the orbital energy becomes less.
how do you find protons in an atom?
Answer:
Protons are always found in the nucleus of an atom.
Explanation:
Protons and neutrons make up the nucleus of an atom, which is in the center. The electrons "orbit" the nucleus.
Answer:
The number of protons, neutrons, and electrons in an atom can be determined from a set of simple rules.
Explanation:
The number of protons in the nucleus of the atom is equal to the atomic number (z). The number of electrons in a neutral atom is equal to the number of protons.
give reason deliquescent substance truns into liquid when exposed to atmosphere air
ppm is used to describe very small amounts of substance?
parts per million (ppm), parts per billion (ppb) and parts per trillion (ppt) are the most commonly used terms to describe very small amounts of substances. a ppm of a chemical in water means that, in a million units of water, there would only be one unit of the chemical.
Is a diamond a homogeneous or heterogeneous mixture or a substance
Answer:
heterogeneous
Explanation:
It's a heterogeneous mixture. Diamond is made of just one element: carbon. Each carbon atom in diamond is connected to four other carbon atoms, in a crystal that extends on and on. There are other forms of pure carbon where the atoms are bonded differently, notably charcoal and graphite.
what is the chimestry
how do you write 652870000 in scientific notations
9
6.5287×10Explanation:This is the correct answerPlz answer me will mark as brainliest
Answer:
Compared to the walls of the right ventricle, the walls of the left ventricles are much thicker.
The plasma carries hormones, which are the body's chemical messengers.
will henry's law not be applicable if the solubility of the gas is very high
Answer:
No
Explanation:
Henry’s law is a gas law which states that at the amount of gas that is dissolved in a liquid is directly proportional to the partial pressure of that gas above the liquid when the temperature is kept constant. The constant of proportionality for this relationship is called Henry’s law constant (usually denoted by ‘kH‘). The mathematical formula of Henry’s law is given by:
P ∝ C (or) P = kH.C
Where,‘
P’ denotes the partial pressure of the gas in the atmosphere above the liquid.‘C’ denotes the concentration of the dissolved gas.‘kH’ is the Henry’s law constant of the gas.Limitations of Henry’s Law
This law is only applicable when the molecules of the system are in a state of equilibrium.Henry’s law does not hold true when gases are placed under extremely high pressure.The law is not applicable when the gas and the solution participate in chemical reactions with each other.The same ball is hit again and experiences a net force of 3.5 N instead. What is the acceleration of the volleyball?
Answer:
I hope this helped :)
Explanation:
a=f/m
a=3.5N/.25 kg
a=14m/s2
The acceleration of the volleyball is 14 m/s²
A force is defined to be a pull or a push acting on an object. The force exerted on an object can be said to be determined if the mass of the object is known.
It can be calculated by using the expression;
Force (F) = mass (m) × acceleration (a)
From the given information;
The net force acting on the ball after it hits again = 3.5 NLet assume that the mass of the ball is 0.25 kg since it is not given∴
The acceleration of the above expression can be computed as:
acceleration (a) = Force (F) / mass (a)
acceleration (a) = 3.5 / 0.25
acceleration (a) = 14 m/s²
Learn more about force here:
https://brainly.com/question/12970081
The pOH of an aqueous solution of 0.480 M trimethylamine (a weak base with the formula (CH3)3N) is .
Answer:
Explanation:
Kb of (CH₃)₃N is 7.4 x 10⁻⁵
initial concentration of (CH₃)₃N a is .48 M
(CH₃)₃N + H₂O = (CH₃)₃NH⁺ + OH⁻
a - x x x
x² / (a - x ) = Kb
x is far less than a so a - x can be replaced by a .
x² / a = Kb
x² = a x Kb = .48 x 7.4 x 10⁻⁵ = 3.55 x 10⁻⁵ = 35.5 x 10⁻⁶
x = 5.96 x 10⁻³
pOH = - log ( 5.96 x 10⁻³ )
= 3 - log 5.96
= 3 - .775
= 2.225
Which of the following characteristics will not help which of the following characteristics WILL NOT help you tell whether two solids are the same or are different substances?
A. Color
B. Hardness
C. Shape
D. Melting point
A rook is dropped into a graduated cylinder filled with 35 mL of water.
What is the volume of the rock? (Hint: 1 ml water = 1 cm?)
40 cm
O 14 cm
O 5 cm
O 35 cm
Answer:
5 cm³.
Explanation:
The following data were obtained from the question:
Volume of water = 35 mL
Volume of water + Rock = 40 mL
Volume of rock =.?
The volume of the rock can be obtained as follow:
Volume of rock = (Volume of water + Rock) – (Volume of water)
Volume of rock = 40 – 35
Volume of rock = 5 mL
Finally, we shall convert 5 mL to cm³. This can be obtained as illustrated below:
1 mL = 1 cm³
Therefore,
5 mL = 5 cm³
Thus, the volume of the rock is 5 cm³.
During photosynthesis, plants and some other organisms use energy from the sun to convert (change): carbon dioxide (CO2) and water (H2O) into ____________ (O2) and __________ (C6H12O6)
Answer:
CO2 + H2O → O2 + C6H12O6
CO2 = carbon dioxide
H2O = water
O2 = oxygen
C6H12O6 = glukose
On average, about ____________ of incoming solar radiation is reflected back to space.
A 50%
B 30%
C 20%
D 10%
How does the motion of particles in the sun’s plasma compare to the motion of particles in a solid?
Particles in both the plasma and a solid move around to fill available space.
Particles in the plasma move randomly, but particles in a solid vibrate in one place.
Particles in the plasma have low kinetic energy, but particles in a solid have high kinetic energy.
Particles in both the plasma and a solid are made up of fast-moving electrons and cations.
Answer:
Particles in the plasma move randomly, but particles in a solid vibrate in one place.
Explanation:
Conductivity is an example of what type of property?
Answer:
A physical property is a characteristic of matter that is not associated with a change in its chemical composition. Familiar examples of physical properties include density, color, hardness, melting and boiling points, and electrical conductivity.
Explanation:
Conductivity is an example of a physical property. Physical properties are characteristics of a substance that can be observed or measured without changing the substance's chemical composition.
Conductivity specifically refers to a material's ability to conduct electricity or heat. Materials with high electrical conductivity allow electricity to flow easily through them, while materials with high thermal conductivity conduct heat efficiently.
Examples of conductive materials include metals like copper and aluminium, which are widely used in electrical wiring and heat transfer applications due to their excellent conductivity properties.
Learn more about Conductivity, here:
https://brainly.com/question/33823148
#SPJ6
Which statement BEST explains why the Moon is visible from the Earth?
1) The Moon reflects light from the Sun.
2) The Moon is always lit up by the Sun for us to see.
3) The Moon reflects light from the Earth.
4) The Moon produces its own light through radiation.
Answer: The answer is the ''The moon is always lit up by the sun for us to see.''
Explanation: The moon is directly illuminated by the sun.
How many of the 7 traits of living things have
Answer:
What do you mean by this?
Explanation:
A sample of an ideal gas has a volume of 2.23 L at 289 K and 1.05 atm. Calculate the pressure when the volume is 1.08 L and the temperature is 304 K. P= atm
Answer:
2.28 atm
Explanation:
V₁ = 2.33L, V₂ = 1.08L
T₁ = 289K, T₂ = 304K
P₁ = 1.05 atm, P₂ = ?
Where V₁ and V₂ are initial and final volume respectively
T₁ and T₂ are initial and final temperature respectively
P₁ and P₂ are initial and final pressure respectively
The formula to be used here is the general gas equation:
P₁V₁/T₁=P₂V₂/T₂
1.05 × 2.23/289 = P₂ × 1.08/304
P₂ × 1.08 × 289 = 1.05 × 2.23 × 304
P₂ = (1.05 × 2.23 ×304) ÷ (1.08 × 289)
P₂ = 711.82 ÷ 312.12
P₂ = 2.28 atm
The specific heat of silver is 0.235 J/gx °C. How much heat is needed to raise the temperature of an 8-gram silver ring by 50°C
Answer:
Heat needed to increase the temperature by 50°C is 94 j.
Explanation:
Given data:
Specific heat of silver = 0.235 j/g.°C
Heat needed to increase temperature = ?
Mass of silver = 8 g
Temperature difference = ΔT= 50°C
Solution:
Formula:
q = mcΔT
c = specific heat capacity of substance
Now we will put the values i formula.
q = 8 g× 0.235 J/g.°C× 50°C
q = 94 J
Heat needed to increase the temperature by 50°C is 94 j.
7. The equation below represents a chemical reaction that occurs in living cells.
CH,26 + 602
6CO2 + 6H,0 + energy
How many atoms are represented in the reactants of this equation?
A=6
B=12
C=24
D=36
Answer:
D
Explanation:
Because i just added all of numbers up
C. 24 if the zero after the 6H, is supposed to be a zero however if it wasnt and u were trying to say h2o it'd be 36
How many grams of MgSO4 should Naomi weigh out to prepare 0.250 L of a 1.25 M solution?
Answer:
Mass of MgSO₄ = 37.61 g
Explanation:
Given data:
Mass of MgSO₄ needed = ?
Volume of solution = 0.250 L
Molarity of solution = 1.25 M
Solution:
Formula;
Molarity = number of moles of solute / L of solution
Now we will put the values in formula:
1.25 M = number of moles of solute / 0.250 L
Number of moles of solute = 1.25 M ×0.250 L
(M = mol/L)
Number of moles of solute = 0.3125 mol
Mass = number of moles × molar mass
Mass = 0.3125 mol × 120.366 g/mol
Mass = 37.61 g
NEED HELP ASAP !
Which best describes an element?
A. elements are chemicals that are pure substance held together by chemical bonds
B. elements are mixtures of protons, neutrons, and electrons in different combination
C. elements are chemicals that are pure substances represented by symbols that have at least one capital letter
D. elements that are chemicals that are formed when temperature change happens or a precipitate forms
Answer:
A. Elements are pure substances.
Explanation:
Out of all four answers A would be best. Hope this helps.
Answer:
B
Explanation:
I think all options can define element in one form or another but an element is characterized by the atomic number it has i.e you will know it's Carbon due to it's number of protons, neutrons and/or electrons.
How can environmental science help you?
Answer:
Organisms and humans depend on each other to get by. Environmental science is important because it enables you to understand how these relationships work.
For example, humans breathe out carbon dioxide, which plants need for photosynthesis. Plants, on the other hand, produce and release oxygen to the atmosphere, which humans need for respiration.
Animal droppings are sources of nutrients for plants and other microorganisms. Plants are sources of food for humans and animals. In short, organisms and humans depend on each other for survival.
Explanation:
What is the final concentration if water is added to 0.25 L of a 8M NaOH solution to make 4.0 L of a diluted NaOH solution?
.25 M NaOH solution
1 M NaOH solution
.5 M NaOH solution
Answer:
0.5 M NaOH solution
Explanation:
Initially, we have 0.25L or 250 mL of 8M NaOH solution
Which means that 1L of this solution would have 8 moles of NaOH
Moles present in 250 mL of solution:
Molarity * Volume( in L)
8 * 0.25 = 2 moles
There is 2 moles of NaOH in 0.25 L of the provided NaOH solution
More water is going to be added to this solution but the number of moles of NaOH will remain the same
now that the solution has a volume of 4L after adding the additional water, we have a 4L solution which contains 2 moles of NaOH
Molarity of the new solution:
Molarity = Number of moles in solution / Volume of solution
Molarity = 2 / 4
Molarity = 0.5 M