I need guidance on this question
Answer:
(C) NO2 has covalent bonds.
A 1 liter solution contains 0.383 M hydrofluoric acid and 0.510 M potassium fluoride.
Addition of 0.096 moles of calcium hydroxide will:
(Assume that the volume does not change upon the addition of calcium hydroxide.)
Raise the pH slightly
Lower the pH slightly
Raise the pH by several units
Lower the pH by several units
Not change the pH
Exceed the buffer capacity
Answer:
Lower the pH slightly
Explanation:
The mixture of HF, hydrofluoric acid and KF, potassium fluoride produce a buffer that is defined for the equilibrium:
HF(aq) → H⁺(aq) + F⁻(aq)
The buffer can maintain the pH of a solution despite the addition of strong bases or acids.
The reaction of HF with Ca(OH)2 is:
2HF + Ca(OH)2 → 2H2O + CaF2
That means the calcium hydroxide is decreasing the concentration of HF. Based on the equilibrium, the H+ and F- ions will decrease in order to produce more HF. As H+ is decreasing due the equilibrium and not for the addition of a strong base, the pH is decreasing slightly.
What compound(s) does pure water contain?
15. Objects can have kinetic energy, potential energy, or both. Energy can be in the form of motion. Energy can
also be stored by objects in various ways, including position, chemical bonds, or physical state.
Which statement is true? And why?
a. An object’s mass has no effect on its potential energy.
b. Potential energy is converted to kinetic energy as a stationary object begins to move.
c. Kinetic energy is converted to potential energy as a stationary object begins to move.
d. A stretched rubber band stores no energy.
Answer: b because Potential energy is converted to kinetic energy as a stationary object begins to move.
Explanation:
HCN
H:C:N:
3.
Is this Lewis Structure correct?
Answer:
No, your missing some bonds
Magnesium hydroxide and sodium hydroxide are both strong bases. The pH of a saturated solution of sodium hydroxide is greater than 14. The pH of a saturated
solution of magnesium hydroxide is about 10.2. Why do the solutions have different pH values?
Answer: Solubility of NaOH is greater and there are more OH- ions in solution.
Explanation: Reactions : NaOH (s) ⇒ Na+ (aq) + OH- (aq)
Mg(OH)2 (s) ⇒ Mg2+ (aq) + 2 OH-(aq)
Although in same amount of moles, Mg(OH)2 produces
two (OH-)-ions in water solution, solubility of Mq(OH)2 is smaller.
Concentration [OH-]ions is smaller in saturated water solution
of Mg(OH)2
Food Science is the study of the physical, biological, and chemical makeup of food; the
causes of food deterioration; and the concepts ulderlying food processing.
True
False
A community located downwind from a coal-fired power plant has seen a recent increase in the number of dead and dying trees. A so scientist measured values for the following parameters before and after the trees died off. Which of the following oil data should be used to determine if the coalfired power plant emiations were the cause of the damage to the trees
a. Moisture content and water retention
b. Parent material composition
c. Pesticide and herbicide residue levels
d. Calcium and aluminum levels
Answer:
Option D, Calcium and Aluminum levels
Explanation:
The coal fired power plant releases huge amount of particulate and gaseous emissions such as mercury, sulphur dioxide, nitrogen oxide etc. When there is rain, these gaseous and particulate matter comes to the ground along with rain water and pollute the soil. There are also chances of acid rain due to the presence of sulphur dioxide. Polluted soil and acid rain negatively impact the growth of the plants and causes leaching of Aluminium thereby decreasing the availability of calcium for the plants. Thus, the trees die. Hence, if the amount of Aluminium and Calcium in soil is determined, one can easily deduce the cause of death of trees.
Hence, option D is correct
How do the equilibrium concentrations of the reactants compare to the equilibrium concentrations of the product?
Answer: It depends equilibrium constant K
Explanation: You need to to have reaction formula.
If K >> 1 then concentrations of products are much bigger than
concentrations of reactants. If K < < 1, concentration of products is small.
What number should be written in front of Na to balance the equation?
Na + MgCl2 → NaCl + Mg
1
2
3
4
In order to balance the chemical equation, the coefficient of Na should be 2.
1. How many grams of water are in a cup containing
0.1 moles of H2O?
Answer:
Explanation:
fdcdf
How much heat must be absorbed by 375 grams of water to raise its temperature by 25 degrees Celsius? Specific heat for water= 4.184 J/g/C or K
Answer:
[tex]3.9*10^4 J[/tex]
Explanation:
See image for explanation!Answer:
[tex]\boxed {\boxed {\sf 39, 225 \ Joules}}}[/tex]
Explanation:
Since we are given the mass, temperature, and specific heat, we should use the following formula to calculate heat energy.
[tex]q=mc \Delta T[/tex]
We have 375 grams of water, the specific heat of water is 4.184 J/g ° C, and the temperature is raised 25 degrees Celsisus. Therefore:
m= 375 g c= 4.184 J/g °C ΔT= 25°CSubstitute the values into the formula.
[tex]q= (375 \ g)(4.184 \ J/g \textdegree C)(25 \textdegree C)[/tex]
Multiply the first two values together. The units of grams will cancel.
[tex]q=1569 \ J/ \textdegree C(25 \textdegree C)[/tex]
Multiply again. This time, the degrees Celsius cancel, so we are left with only the units of Joules.
[tex]q= 39225 \ J[/tex]
39,255 Joules of heat must be absorbed by the water.
mrs tuckers class is doing an experiment they fill up a cup with ice water they measure the temperature of both the water and the classroom after one hour . what will mrs tucker observe about the temperature of ice water after one hour
A. The temperature will increase
B. The temperature Will remain the same
C. The temperature will decrease greatly
D. The temperature Will decrease slightly
Answer:
Ofc D. bc if the temp decreases, that means it is getting colder u dummy! But if it increases, it is getting warmer.
Explanation:
I got it right on USATestprep for using common sense, mark me the brainliest.
Which of the following substances can be dissolved in pure water to give a basic solution?
Hydrogen chloride
Sodium bromide
Sodium hydroxide
Sodium chloride
I think it's sodium hydroxide
Explanation:
sodium hydroxide is a base
Ice melts after adding heat. The free energy is ————— !
A. Exothermic
B. Not temperature dependent
C. Temperature dependent
D. Depended on how it is heated
E. React with active metals to form h2 gas
F. Endothermic
At a certain temperature the vapor pressure of pure benzene is measured to be . Suppose a solution is prepared by mixing of benzene and of heptane . Calculate the partial pressure of benzene vapor above this solution. Round your answer to significant digits.
Answer:
P(C₆H₆) = 0.2961 atm
Explanation:
I found an exercise pretty similar to this, so i'm gonna use the data of this exercise to show you how to do it, and then, replace your data in the procedure so you can have an accurate result:
"At a certain temperature the vapor pressure of pure benzene (C6H6) is measured to be 0.63 atm. Suppose a solution is prepared by mixing 79.2 g of benzene and 115. g of heptane (C7H16) Calculate the partial pressure of benzene vapor above this solution. Round your answer to 2 significant digits. Note for advanced students: you may assume the solution is ideal".
Now, according to the data, we want partial pressure of benzene, so we need to use Raoul's law which is:
P = Xₐ * P° (1)
Where:
P: Partial pressure
Xₐ: molar fraction
P°: Vapour pressure
We only have the vapour pressure of benzene in the mixture. We need to determine the molar fraction first. To do this, we need the moles of each compound in the mixture.
To get the moles: n = m / MM
To get the molar mass of benzene (C₆H₆) and heptane (C₇H₁₆), we need the atomic weights of Carbon and hydrogen, which are 12 g/mol and 1 g/mol:
MM(C₆H₆) = (12*6) + (6*1) = 78 g/mol
MM(C₇H₁₆) = (7*12) + (16*1) = 100 g/mol
Let's determine the moles of each compound:
moles (C₆H₆) = 79.2 / 78 = 1.02 moles
moles (C₇H₁₆) = 115 / 100 = 1.15 moles
moles in solution = 1.02 + 1.15 = 2.17 moles
To get the molar fractions, we use the following expression:
Xₐ = moles(C₆H₆) / moles in solution
Xₐ = 1.02 / 2.17 = 0.47
Finally, the partial pressure is:
P(C₆H₆) = 0.47 * 0.63
P(C₆H₆) = 0.2961 atmHope this helps
UV light can damage biological molecules because it has sufficient energy to break bonds within molecules. A carbon-carbon single bond typically requires 348 kJ/mol of energy to break it. What is the longest wavelength of light with energy sufficient to break this bond
Answer:
5.72 × 10⁻³¹ m
Explanation:
Step 1: Given and required data
Energy to break 1 mole of C-C single bonds (E): 348 kJPlanck's constant (h): 6.63 × 10⁻³⁴ J.sSpeed of light (c): 3.00 × 10⁸ m/sStep 2: Calculate the longest wavelength of light (λ) with energy sufficient to break this bond
We will use the Planck-Einstein relation.
E = h × c/λ
λ = h × c/E
λ = (6.63 × 10⁻³⁴ J.s) × (3.00 × 10⁸ m/s)/(348 × 10³ J) = 5.72 × 10⁻³¹ m
How many moles are in 3.72 x 10^27 atoms of iron?
Answer: There are [tex]0.617 \times 10^{4}[/tex] moles present in [tex]3.72 \times 10^{27}[/tex] atoms of iron.
Explanation:
According to the mole concept, there are [tex]6.022 \times 10^{23}[/tex] atoms present in one mole of a substance.
Hence, moles present in [tex]3.72 \times 10^{27}[/tex] atoms are calculated as follows.
[tex]Moles = \frac{3.72 \times 10^{27}}{6.022 \times 10^{23}}\\= 0.617 \times 10^{4} mol[/tex]
Thus, we can conclude that there are [tex]0.617 \times 10^{4}[/tex] moles present in [tex]3.72 \times 10^{27}[/tex] atoms of iron.
what do adamantium,vibranium and unobtainum have in common
Answer:
they're all fake
Explanation:
in writing a chemical equation that produces hydrogen gas, the correct representation of hydrogen gas is
a.H
b.2H
c.H2
d.OH
Answer:
h2
Explanation:
Mercury: Mineral or Not Mineral? Mineral Not Mineral
Answer:
not a mineral but is a “mineraloid
Explanation:
not mineral
Explanation: its an element but it is not a mineral
The exact mechanism of this reaction is a little complicated, as it involves the copper ions. However, the process involves the formation of small amounts of bromine in situ. Draw the mechanism of the bromination of 4-tert-butyl phenol with Br2. -g
Answer:
see picture below
Explanation:
The mechanism is in the following picture.
In the first step, the lone pair of oxygen (from the OH) as it's a strong activating group in the molecule, will go to the ring. This will cause that the double bond of the ring of the ortho position, attacks as nucleophyle to the Br2, causing the breaking of the bond.
In the second step, the bromine ion substract the hydrogen from the ortho position, and then, by resonance, the pair of electrons returns to the oxygen of the phenol.
What do greenhouse gases do on Earth?
Answer:
It holds heat from the sun close to Earth.
Explanation:
Hope this helps and have a great day. :)
Give the ratio that balances out the following equation: ___Cr + ___Pb(NO3)4 ---> ___ Cr(NO3)3 + ____ Pb
Answer: Ratio : 4, 3, 4, 3 are the answers.
Explanation:
Do u believe that you are beautiful/handsome?
Yes or No?
In which phase of wound healing is fibrin most involved?
Answer:
Finally, coagulation occurs and reinforces the platelet plug with threads of fibrin which are like a molecular binding agent. The hemostasis stage of wound healing happens very quickly.
Explanation:
Hope it helps u
FOLLOW MY ACCOUNT PLS PLS
Is This An Igneous Rock Or Metamorphic Or Sedimentary?
Answer:
Metamorphic
Explanation:
Answer: thats metamorphic rock
give an example of a primary income from the rest of the world
Answer:
(1) Income Associated with the Production Process
(a) Compensation of employees
(b) Taxes and subsidies on products and
production .
(2) Property Income
(a) Investment income:
• Dividends and withdrawals from income of
quasi-corporations
• Reinvested earnings
• Interest
(b) Rent .
I hope this is correct :-)
How many moles of sodium hydroxide would have to be added to 150 mL of a 0.483 M acetic acid solution, in order to prepare a buffer with a pH of 4.480
Answer:
0.068 moles of sodium hydroxide would have to be added to 150 mL of a 0.483 M acetic acid solution
Explanation:
As we know
pH = pKa + log [salt]/[acid]
4.480= 4.74 + log [salt]/[acid]
log [salt]/[]acid] = -0.06
[salt]/[acid] = 0.87
moles acid = 0.150 L x 0.483 mol/L = 0.07245 moles acid
x/0.07245-x = 0.87
X- 0.07245 X = 0.87 *0.07245
X = 0.068 moles
Which of the following is true for a gas under conditions of very high pressure? (5
points)
1) PV > nRT, because the real volume of the gas would be more than the ideal
volume.
2) PV = nRT, because intermolecular forces are considerable at very high
pressures.
3) PV = nRT, because all gases behave as ideal gases at very high pressures.
04) PV = nRT, because the volume of the gas would become negligible.
Answer:
1) PV > nRT, because the real volume of the gas would be more than the ideal
volume.
Explanation:
According to the ideal gas equation; PV = nRT. Let us recall that this equation only holds under ideal conditions.
Gases exhibit ideal behavior under high temperature and low pressure. At higher pressure, the real volume of the gas is larger than the ideal volume of the gas.
Thus, at high pressure, PV > nRT, because the real volume of the gas would be more than the ideal volume.
Answer:
1) PV > nRT, because the real volume of the gas would be more than the ideal volume.
Explanation:
just took the test :)