Answer:
The pigment that causes leaves to be green is chlorophyll. ... As chlorophyll goes away, other pigments start to show their colors. This is why leaves turn yellow or red in fall. In fall, plants break down and reabsorb chlorophyll, letting the colors of other pigments show through.
Question List
Question 4 of 8
Total Points: 0 out of 80
Calculate the volume that will be occupied by
240 mL of hydrogen, measured at 360 mm Hg, when
the pressure is changed to 1080 mm Hg.
Answer:
80 mL
Explanation:
Step 1: Given data
Initial pressure of hydrogen (P₁): 360 mmHgInitial volume of hydrogen (V₁): 240 mLFinal pressure of hydrogen (P₂): 1080 mmHgFinal volume of hydrogen (V₂): ?Step 2: Calculate the final volume of hydrogen
If we assume ideal behavior and constant temperature, we can calculate the final volume occupied by hydrogen using Boyle's law.
P₁ × V₁ = P₂ × V₂
V₂ = P₁ × V₁/P₂
V₂ = 360 mmHg × 240 mL/1080 mmHg = 80 mL
how many mg are in 125ml of
phosphoric acid?
Answer:
125000mg
Explanation:
1ml = 1000mg
125(1000) = 125000mg
Which layer of the Earth includes the crust? a atmosphere b hydrosphere c asthenosphere d lithosphere
Answer:
D
Explanation:
Hope that helps :)
A voltaic cell is constructed in which the anode is a Fe|Fe2 half cell and the cathode is a Cd|Cd2 half cell. The half-cell compartments are connected by a salt bridge. (Use the lowest possible coefficients. Be sure to specify states such as (aq) or (s). If a box is not needed, leave it blank.) The anode reaction is:
Answer: The Anode reaction is [tex]Fe(s)\rightarrow Fe^{2+}(aq)+2e^-[/tex]
Explanation:
Oxidation-reduction reaction or redox reaction is defined as the reaction in which oxidation and reduction reactions occur simultaneously.
Oxidation reaction is defined as the reaction in which a substance looses its electrons.Oxidation occurs at anode.
Anode : [tex]Fe(s)\rightarrow Fe^{2+}(aq)+2e^-[/tex]
Reduction reaction is defined as the reaction in which a substance gains electrons. Reduction occurs at cathode.
Cathode : [tex]Cd^{2+}(aq)+2e^-\rightarrow Cd(s)[/tex]
What is the change in enthalpy when 180 g of water vapor condenses at 100°C? (AH, = 40.67 kJ/mol)
a. 565 kJ
b. -565 kJ c.
-407 kJ d.
407 kJ
Answer:
[tex]Q=-407kJ[/tex]
Explanation:
Hello there!
In this case, considering that the heat has two forms, sensible (variable temperature) and latent (constant temperature), we can notice that phase changes account for latent heat as the temperature remains the same. In such a way, given the enthalpy of vaporization of water, 40.67 kJ/mol, the enthalpy of condensation (reverse process) is the negative value, -40.67 kJ/mol; therefore, the associated latent heat would be:
[tex]Q=180g*\frac{1mol}{18.02g} *-40.67\frac{kJ}{mol} \\\\Q=-407kJ[/tex]
Best regards!
The answer is
C) -407 kJ d
Arrange the following substance into acid,base and neutral. sodium chloride, tomato juice, vinegar,sea water,bicorbonate of sodium
Answer:
sodium chloride: neutral.
tomato juice: acid.
vinegar: acid.
sea water: base.
bicarbonate of sodium: base.
Explanation:
Hello there!
In this case, in agreement to the definition of the pH, as the measure of the acidity and basicity of a substance; it is important to recall that pH's below 7 stand for acidic substances and pH's above 7 stand for basic substances, whereas a pH of 7 defines a neutral one. In such a way, given the pH's of the given substances, 7, 4.05 to 4.65, around 2.5, about 8.1 and about 8.3 respectively for sodium chloride, tomato juice, vinegar, sea water, bicarbonate of sodium, it is possible to assert:
sodium chloride: neutral.
tomato juice: acid.
vinegar: acid.
sea water: base.
bicarbonate of sodium: base.
Best regards!
Helllllp me please
Part D ends with neon Express your answer as an integer. 20
Answer:
attach file please
Nitrous oxide (N2O), more commonly known as laughing gas, is used as a mild sedatitive during various dental procedures.As a gas, it has a densityof 1.977 x 10-3g/mL.Wheniron is exposed to oxygen it forms rust (Fe2O3), which is a solid and has a density value of 5.25 g/mL.Why are the density values so different among these substances?
a)The metal atoms weigh more than the atoms of the gas.
b)The metal forms metallic bonds which are more greatly affected by gravity, increasing the mass.
c)The metal is a solid, and solids weigh more based on the principles of their states of matter.
d)There are fewer gas particles than solid particles in the same volume.
Answer:
B.
Explanation:
The metal forms metallic bonds which are more greatly affected by gravity, increasing the mass.
Suppose you have a 1:1:1 by weight mixture of three solid compounds, salicylic acid 4-nitroaniline naphthalene. You dissolve 1 gram of this mixture in diethyl ether, and place a tiny drop of the ether solution on a TLC plate. After developing the TLC plate, you see three spots. Which compound would would you expect to have the largest Rf value
Answer:
The correct answer is - 4-nitroaniline.
Explanation:
It is given that all three solid compounds salicylic acid + 4-nitroaniline + naphthalene are equal in the ratio in the mixture and then 1 gram of this mixture is dissolved in the diethyl ether and run a drop of the solution on TLC plate. This plate shows three spots.
The salicylic acid and naphthalene would stay dissolved in the diethyl ether solution due to the 4-nitroaniline could be extracted by adding aqueous acid and involve in the aqueous layer and thus spot of 4-nitroaniline would be with largest Rf value.
What is the volume of .80 g of O2 gas at STP?
Answer:0.56L
Explanation:Molar mass of O2=32
N=0.8/32
N=0.025
V=0.025 x 22.4=0.56L
In a sample of neon, carbon, and oxygen gas, the total pressure is 9 atm.
The partial pressure of neon is 2 atm and the partial pressure of oxygen is 2
atm. What is the partial pressure of carbon?
9 atm
3 atm
5 atm
4 atm
Answer:
5 atm
Explanation:
add boh partial pressures and subtract from total pressure
2. Calculate the concentration (in molarity) of a NaOH solution if 25.0 mL of the solution are needed to neutralize 17.4 mL of a 0.312 M HCl solution.
Answer:
0.217 M NaOH
Explanation:
M1V1 = M2V2
M1 = 0.312 M HCl
V1 = 17.4 mL HCl
M2 = ?
V2 = 25.0 mL NaOH
Solve for M2 --> M2 = M1V1/V2
M2 = (0.312 M)(17.4 mL) / (25.0 mL) = 0.217 M NaOH
Question 10 of 23
Which characteristic makes a digital signal more useful than an analog signal
for storing information?
A. A digital signal includes a spectrum of colors.
B. A digital signal is more difficult to copy.
C. A digital signal cannot be heard by humans.
O D. A digital signal moves between a discrete number of values.
Answer: O D. A digital signal moves between a discrete number of values.
Explanation:
The digital signals are considered more reliable over the analog signals as they encode the information in a coded form. The bits or samples of the data are transmitted and converted into digital and numerical value. The stream of encoded data is in the form of continuous data at regular time intervals. It provides information in waveform and the data is in compact form. The data is in the form of binary bits 0 and 1 so greater the number of bits greater will be the greater will be the resolution of the information.
5 ways light changes objects
Which term describes something that displays all the characteristics of life?
a.homeostasis
b.organism
c.stimulus
d.unicellular
Select the valid ways to make an ammonia/ammonium buffer for use in the laboratory. Mix equal volumes of 1 M NH3 and 0.01 M NH 4. Mix some volume of 1 M NH3 with half as much 1 M HCl. Mix equal volumes of 1 M NH3 and 1 M NH 4. Mix equal volumes of 1 M NH3 and 1 M HCl.
Answer:
The answer is "Option b and Option c".
Explanation:
This buffer is a buffer of ammonia and ammonium ion. Thus it requires the solution [tex]NH_3 \ \ and \ \ NH_4^{+}[/tex].
In point 1:
The solution containing [tex]NH_3 \ \ and \ \ NH_4^{+}[/tex] at 1M concentration would be given by mixing the two solutions. Thus, this buffer is a legitimate route.
In point 2:
It gives the ions you want but they are not the same.
In point 3:
[tex]1 M[/tex] [tex]NH_3[/tex] and [tex]1 M[/tex][tex]HCl[/tex] volume would not produce the same [tex]NH_3 \ \ and \ \ NH_4^{+}[/tex] concentrations. Therefore, this buffer isn't a valid route.
In point 4:
Some [tex]1 M[/tex] [tex]NH_3[/tex] volume and half [tex]HCl[/tex] . This offers the same rate as half.
Identify the most and the least basic compound in each of the following sets. Leave the remaining answer in each set blank. a) Sodium acetate: _______ Ammonia: _______ Sodium ethoxide: _______ b) Sodium acetate: _______ Sodium chloroacetate: _______ Sodium fluoroacetate: _______ c) Sodium acetate: _______ Sodium methoxide: _______ Sodium phenoxide:
Answer:
The correct answer is -
a) Sodium acetate: least Ammonia: _______ Sodium ethoxide: most
b) Sodium acetate: most Sodium chloroacetate: _______ Sodium fluoroacetate: least
c) Sodium acetate: least Sodium methoxide: most Sodium phenoxide:
Explanation:
A) In this case the basicity can be found by the stability of the base, Sodium acetate is the most stable base due to resonance stabilization of acetate anion. Sodium acetate is the least basic as the lone pair of electrons involved in the resonance here. An ethoxide ion has more electrons to donate an electron pair easily.
Thus, the correct answer is - Sodium acetate is the least basic while sodium ethoxide is the most basic.
B) Fluroacetate gives a very strong acid and the acetate gives the least strong acid among all three as described in case of a), thus, the most basic is acetate and the least is fluoroacetate.
]C) comparing the acidity of the acids formed by the addition of a proton to the anions is an easy and correct way to find the basicity of compounds.
Acetate ion adds a proton ⇒ acetic acid
methoxide adds a proton ⇒ methanol
phenoxide ion adds proton ⇒ phenol
As it is known that the stronger the acid, the weaker is the conjugate base formed by the loss of the proton.
acetic acid is the strongest acid because it can easily give up its proton to form acetate. Methanol is the weakest among all three and hence methoxide anion is the strongest base.
Thus, the correct answer is - sodium acetate is the least basic while sodium methoxide is the most basic.
what do you mean by carrier
Answer:
1 : one that carries : bearer, messenger. 2a : an individual or organization engaged in transporting passengers or goods for hire. b : a transportation line carrying mail between post offices.
What mass of nitrogen (N2) is needed to produce 0.125 mol of ammonia (NH3)? Input a numerical answer only. N2 + 3H2 ---> 2NH:
Please help me
What is the mass in grams of 8.65 mol C8H18?
Answer in standard notation to zero decimal places.
PLEASE HELP THIS IS DUE AT 11:59 AT MIDNIGHT AND IM FREAKING OUT
Answer:
m = 998 g
Explanation:
Hello there!
In this case, according to the definition of the molar mass as the mass of one mole of the compound, it is possible to state the 1 mole of C8H18 has a mass of 114.26 grams; therefore, the mass in 8.65 moles turn out to be:
[tex]m=8.65mol*\frac{114.26g}{1mol}\\\\m=998g[/tex]
In agreement to the notation requirement.
Best regards!
what is an example of an electrolyte solution?
Answer:
nacl with water
they are capable of conducting electricity
True or false. Law of action/reaction: for every action there is an equal and the same reaction. Pls don’t give me a link and tell me the answe
If the solubility of salicylic acid is 77.8 g/L of water at 100oC and 1.4 g/L of water at 10oC, a) calculate the minimum amount (in mL) of boiling water necessary to dissolve 2.0 g of impure salicylic acid for recrystallization. b) If the solution is cooled to room temperature and then to 10oC with an ice/water bath, what is the maximum amount of solid salicylic acid isolated after vacuum filtration
Answer:
a. 25.7mL are necessaries.
b. 1.964g of salicylic acid can be isolated.
Explanation:
a. As the solubility of salicylicic acid in boiling water is 77.8g/L, to dissolve 2.0g of salicylic acid are necessaries:
2.0g * (1L / 77.8g) = 0.0257L =
25.7mL are necessariesb. Then, at 10°C the solution just can dissolve 1.4g/L, that is:
0.0257L * (1.4g/L) = 0.036g of salicylic acid are dissolved.
And will precipitate:
2.0g - 0.036g =
1.964g of salicylic acid can be isolatedA truck accelerates at a rate of 14 m/s2 . The truck weighs 17000 kg. What is the amount of force
necessary for the truck to accelerate at this rate?
Answer:
238000 N
Explanation:
Use F=ma
Mass= 17000 kg
Accel.= 14 m/s²
. Give an example of a salt that is less soluble when the temperature increases
Answer:
cerium (iii) sulfate is less soluble
Answer:
cerium sulphate is less solube when the temperature increase
Help meee??
HNO 3 is an example of Select one :
Triprotic Acid
O Diprotic Acid
O Monoprotic Acid
Tetraprotic Acid
A mole equals 6.02 x 10^23 . Answer these questions below.
1. How many ants are in 1.25 moles of ants?
2. How many moles of pencils are in 4.92 * 10^26 pencils?
3. How many molecules are in 0.26 moles of molecules?
4. How many moles of molecules are in 3.46 * 10^19 molecules?
5. 5.3 * 10^20 atoms are equal to how many moles of atoms?
6. 0.11 moles of atoms are equal to how many atoms?
Answer:
1. 1.25 mol ants x 6.02*10^23 ants/1 mol ants = 7.53*10^23 ants
2. 4.92*10^26 pencils x 1 mol pencils/6.02*10^23 pencils = 817 mol pencils
3. 0.26 mol molecules x 6.02*10^23 molecules/1 mol molecules = 1.6*10^23 molecules
4. 3.46*10^19 molecules x 1 mol molecules/6.02*10^23 molecules = 5.75*10^-5 mol molecules
5. 5.3*10^20 atoms x 1 mol atoms/6.02*10^23 atoms = 8.8 mol atoms
6. 0.11 mol atoms x 6.02*10^23 atoms/1 mol atoms = 6.6*10^22 atoms
I would suggest looking into "dimensional analysis" for help with this type of material. Dimensional analysis will stick with you all throughout chemistry, so picking it up will be extremely beneficial.
Mixtures that would be considered buffers include which of the following? I. 0.10 M HCl + 0.10 M NaCl II. 0.10 M HF + 0.10 M NaF III. 0.10 M HBr + 0.10 M NaBr
Answer:
II. 0.10 M HF + 0.10 M NaF.
Explanation:
A buffer system may be formed in one of two ways:
A weak acid and its conjugate base.A weak base and its conjugate acid.Which of the following mixtures could be considered a buffer?
I. 0.10 M HCl + 0.10 M NaCl. No, because HCl is a strong acid.
II. 0.10 M HF + 0.10 M NaF. Yes, since HF is a weak acid and F⁻ (coming from NaF) is its conjugate base.
III. 0.10 M HBr + 0.10 M NaBr. No, because HBr is a strong acid.
if 23.1g of O2 occupies a volume of 5.0L at a particular temperature and pressure, what volume will 2.50g of Oxygen gas occupy under the same conditions?
Answer:
0.54 L
Explanation:
First we convert the given masses of O₂ into moles, using its molar mass:
23.1 g ÷ 32 g/mol = 0.722 mol2.50 g ÷ 32 g/mol = 0.078 molThen we can solve the problem using Avogadro's law, which states:
V₁n₂=V₂n₁Where:
V₁ = 5.0 Ln₂ = 0.078 molV₂ = ?n₁ = 0.722 molWe input the data:
5.0 L * 0.078 mol = V₂ * 0.722 molAnd solve for V₂:
V₂ = 0.54 Lwhat role does the grass play in the food web?
A. Producer B. Primary Consumer C. secondary Consumer D. Decomposer
Answer:
Producer
Explanation:
I took the test :)