How many internal parts or “organelles” are there in a plant cell?
please i need a answer!
Answer: it has 2 parts
Explanation:
Firstly, plant cells have a cell wall that surrounds the cell membrane, whereas animal cells do not. Plant cells also possess two organelles that animal cells lack: chloroplasts and a large central vacuole
I need help please. No links/ irrelevant answers or I will report you
Data:
2Fe(s) + O2(g) => 2FeO(s) ΔH = -545.6 kJ
4Fe(s) + 3O2(g) => 2Fe2O3(s) ΔH = -1,643.6 kJ
3Fe(s) + 2O2(g) => Fe3O4(s) ΔH = -1,117.7 kJ
Given the data above, determine the heat of reaction, ΔH, for the reaction:
2 Fe3O4(s) => 2 Fe2O3(s) + 2 FeO(s)
Answer:
ΔH = 46.2 kJ
Explanation:
Hello there!
In this case, according to the given set of reactions and the required one, it is possible to apply the Hess' rule in order to realize the following manipulations to obtain the required reaction:
1. Keep this reaction as it is.
2Fe(s) + O2(g) => 2FeO(s) ΔH = -545.6 kJ
2. Keep this reaction as it is.
4Fe(s) + 3O2(g) => 2Fe2O3(s) ΔH = -1,643.6 kJ
3. Reverse double this reaction so that we obtain:
2Fe3O4(s) => 6Fe(s) + 4O2(g) ΔH = -(-1,117.7 kJ)*2=2235.4kJ
Add them up to obtain:
2Fe(s) + O2(g) + 4Fe(s) + 3O2(g) + 2Fe3O4(s) => 6Fe(s) + 4O2(g) +2Fe2O3(s) + 2FeO(s)
Simplify common terms to obtain:
2 Fe3O4(s) => 2 Fe2O3(s) + 2 FeO(s)
Therefore, the enthalpy of such reaction is:
ΔH = 2235.4kJ -545.6 kJ -1,643.6 kJ
ΔH = 46.2 kJ
Best regards!
explain why people are concerned with the rising level of carbon dioxide in the atmosphere (CO2). What are engineers doing to rebalance the carbon cycle? What can you do to help rebalance the carbon cycle?
Answer:
People are concerned with the rising level of carbon dioxide in the atmosphere because it could be leading to global warming, which is the observed increase of the Earth's temperatures. Engineers are working to rebalance the carbon cycle by designing appliances, buildings and homes that use less energy.
Explanation:
I don’t know if I’m right..........
A 250mL beaker is submerged in a large container of Liquid A and turned upside down, and another 250mL beaker is submerged and turned upside down in a large container of Liquid B. Hydrogen H2 gas is bubbled into each upside-down beaker until 100mL of liquid has been displaced. The masses mA and mB of hydrogen inside each beaker is then chemically determined. Note for advanced students: you may assume the solubility of H2 in either liquid is very low.
a. mx will be greater than my
b. mx will be less than my
c. mx will be equal to my
d. It's impossible to predict whether mx or my will be greater without more information.
Answer:
Mx will be less than My.
Explanation:
The correct option is - Mx will be less than My.
Because, liquid X have been higher viscosity and vapor pressure than liquid B.
Vapor pressure of liquid A is greater, so the amount of liquid X will vaporized greater and H2 gas has been displaced greater from the beaker as compared to liquid Y.
The amount of H2 in liquid Y remains greater in beaker as compared to liquid X.
So, Mx will be less than My.
How do organisms get their genes?
ANSWER CAREFULLY!!!
Answer:
born
Explanation:
they get bornnnnnnnn
Answer:
by their mummy and daddy
Explanation:
if their mummy has blue eyes but their Duddy has brown eyes if the child has brown eyes then the dud has the most dominatetrait
have a good day mate
2. According to Newton's second law of motion, in which of these situations is the object
accelerating? a. A book on a shelf b. A rock sitting on the ground c. A helium balloon tied to a
lamppost d. A ball that has been thrown upward
Answer:
the Answer is A ball that has been thrown upward
N₂ + 3H₂ --> 2NH₃
If 207.0 g of H₂ reacts, what mass of NH₃ is produced?
Answer:
69mol
Explanation:
The balanced chemical equation given in this question is as follows;
N₂ + 3H₂ → 2NH₃
The above balanced equation shows that 3 moles of hydrogen gas (H2) reacts to produce 2 moles of ammonia (NH3).
To convert the given mass of hydrogen to moles, we use the following formula:
mole = mass/molar mass
Molar mass of H2 = 2g/mol
mole = 207/2
= 103.5mol
If 3 moles of H2 produce 2 moles of NH3,
Then, 103.5mol of H2 will produce 103.5 × 2 / 3
= 207/3
= 69mol
Plz help me well mark brainliest if correct!!
Answer:
A
Explanation:
Waxing means getting bigger.
Waning is.. you guessed it... the exact opposite.
Answer:
a
Explanation:
..........................
Is c6h4cl2 soluble in water?
Answer:
slightly but poorly
Explanation:
it is a white crystalline solid that is practically insoluble in water and soluble in ether, chloroform, carbon disulfide, benzene, alcohol and acetone.
Can someone help me I am stuck on this question it would mean the world if u helped me =) have a nice day!
Plz help me I am!!!!
What would happen to the position of the equilibrium when the following changes are made to the reaction below?
2HgO(s) ↔ Hg(l) + O2(g)
1.) The pressure on the system decreases.
The water treatment plant adds chlorine gas to the municipal water supply to
control microorganisms. If a technician adds Cl2 at a rate of 1 mg per liter of water,
what is the molar concentration of chlorine in the drinking water?
Answer:
1 × 10⁻⁵ M
Explanation:
Step 1: Given data
Concentration of chlorine: 1 mg/LStep 2: Convert the concentration of chlorine from mg/L to g/L
We will use the conversion factor 1 g = 10³ mg.
1 mg/L × 1 g/10³ mg = 1 × 10⁻³ g/L
Step 3: Convert the concentration of chlorine from g/L to mol/L (molar)
We will use the molar mass of chlorine: 70.91 g/mol.
1 × 10⁻³ g/L × 1 mol/70.91 g = 1 × 10⁻⁵ mol/L = 1 × 10⁻⁵ M
A gas is contained in a thick-walled balloon. When the pressure changes from ___ kPa to 114 kPa, the volume changes from 0.654 L to 1.32 L and the temperature changes from 596 K to 715 K.
Answer: 191.8
Explanation:
Answer:
191.8
Explanation:
I know the answer is correct I got the exact same one :)
HELP ASAP no links or I will report
Answer:
50 feet
Explanation:
I got it right
Brainliest plz
Answer: 50 feet
Explanation:
Formula mass of Ca(NO2)2
Answer: 132.1 g/mol
Explanation: 40.08 + 2·(14.01+2·16)
If 74.5 m of oxygen are collected at a pressure of 98.0 kPa, what volume will the gas occupy if the
pressure is changed to 90.4 kPa?
Answer:
80.8 mL
Explanation:
From the question given above, the following data were obtained:
Initial volume (V₁) = 74.5 mL
Initial pressure (P₁) = 98.0 kPa
Final pressure (P₂) = 90.4 kPa
Final volume (V₂) =?
The final volume of the gas can be by using the Boyle's laws equation as follow:
P₁V₁ = P₂V₂
98 × 74.5 = 90.4 × V₂
7301 = 90.4 × V₂
Divide both side by 90.4
V₂ = 7301 / 90.4
V₂ = 80.8 mL
Thus, the volume of the gas is 80.8 mL
Which sound frequency with a human ear be able to detect? Select ALL correct answers.
100 Hertz
1,000 Hertz
10,000 Hertz
100, 000 Hertz
The answers are 100, 1,000, 10,000 if your are with K12
Answer:
100 HZ 1,000 HZ 10,000 HZ there you go :)
Answer:
100 hertz, 1,000 hertz, and 10,000 hertz
Explanation:
I took the k12 test :)
Calculate the mass (grams) of 0.750 moles of Al2(Cr2O7)3
Answer:
526g is the mass of this sample
Explanation:
To solve this question we must, as first, find the molar mass of Al₂(Cr₂O₇)₃ using the periodic table. The molar mass is defined as the mass of this compound per mole. With this value we can find the mass in 0.750 moles as follows:
Molar mass Al₂(Cr₂O₇)₃
2Al = 2*26.98g/mol = 53.96g/mol
6 Cr = 6*51.9961g/mol = 311.9766g/mol
21 O = 21*15.999g/mol = 335.979g/mol
53.96g/mol + 311.9766g/mol + 335.979g/mol
= 701.9156g/mol
The mass of 0.750 moles is:
0.750 moles * (701.9156g / mol) =
526g is the mass of this sampleIn the process of photosynthesis, plants take in carbon dioxide (CO2) from the atmosphere and water (H2O) from the soil. Using the energy of sunlight, plants build molecules of glucose (C6H12O6) and oxygen (O2).
Select one:
a.
Plants absorb Carbon Dioxide which increases the amount of carbon in the atmosphere.
b.
Plants produce Carbon Dioxide which increases the amount of carbon in the atmosphere.
c.
Plants absorb Carbon Dioxide which reduces the amount of carbon in the atmosphere.
d.
Plants produce Carbon Dioxide which reduces the amount of carbon in the atmosphere.
Answer:
C
Explanation:
thts the right answwer im sure
Answer:
C
Explanation:
They take in carbon dioxide and make an oxygen. That's why they are encouraging people to plant. Less CO2 more oxygen
You are attempting the reduction of quinone with sodium borohydride. After adding the 0.05 g of NaBH4 you note that the solution remains yellow. Following the procedure, you continue to add increments of 0.05 g NaBH4. You note that the yellow color remains even after the addition of 0.10 g of extra NaBH4. Several students around you are experiencing a similar problem. Propose a cause for this and suggest a solution.
Answer:
When benzoquinone reacts with sodium borohydride, which is yellow in color, white and colorless hydroquinone is formed.
Explanation:
The reaction described below should occur. However, even as we add more sodium borohydride, the color stays yellow. This implies that the solution must contain unreacted benzoquinone. Furthermore, NaBH4 is a kind of hydride (H-), and the reaction starts with the addition of hydride.
The acid oxygen is protonated once more to produce a neutral primary alcohol. As sodium borohydride is a reducing agent, adding more will not cause the benzoquinone to react with it, increasing the amount of NaBH4 will not affect the color of the benzoquinone.
Often, benzoquinone is very vulnerable to solid minerals, acids, and alkalis, causing it to condense and decompose.
Air pressure is greatest ____ because there are more molecules of air pushing down from above.
a.
at the top of the mountain
c.
in the troposphere
b.
at sea level
d.
in the exosphere
Please select the best answer from the choices provided
Answer:A
Explanation:
I just know it
Answer:
The correct answer is B
You have 1.2 x 10^25 particles of NiCO3. How many grams are present?
Answer:
2365.0 g
Explanation:
First we convert 1.2 x 10²⁵ particles into moles, using Avogadro's number:
1.2 x 10²⁵ particles ÷ 6.023x10²³ particles/mol = 19.9 molThen we convert 19.9 moles of NiCO₃ into grams, using the molar mass of NiCO₃:
NiCO₃ Molar Mass = 118.702 g/mol19.9 mol * 118.702 g/mol = 2365.0 gBased on this information, which hypothesis best predicts how a change to the gene could affect people who do not produce enough lactase?
Answer:
B
Explanation:
I had same question
The strength of an acid is affected by the polarity of the bond connected to the acidic hydrogen. The more highly polarized this bond, the more easily the hydrogen is ionized. Electronegative atoms or groups of atoms present in the structure of an acid can act to withdraw electrons and produce additional polarization. Two common groups of acids to which this principle can be applied are oxoacids and carboxylic acids. In the latter group, the length of the hydrocarbon chain in a carboxylic acid has very little effect on acid strength Longer chains may slightly diminish acidity. Bases act as hydrogen ion acceptors because of the unshared electron pass in their structure. Any group present in a base that withdraws electrons makes these electron pairs less available to accept a hydrogen ion. In contrast, any group that can act as an electron donating group such as hydrocarbon groups (usually represented as II) can increase the base strength. Thus, the addition of electronegative atoms or groups of atoms to the structure of a base decreases the base strength and electron donating groups increase base strength. Many common weak bases are derivatives of ammonia, in which H atom(s) of NH_2 are replaced with other groups.
Arrange the following oxoacids in order of decreasing acid strength. Rank from strongest to weakest acid.
HBrO
HClO
HClO3
HClO2
Answer:
HClO3>HClO2>HClO>HBrO
Explanation:
Hello there!
In this case, in agreement to the given information and the reported acidic dissociation constant (Ka) for these acids, which are shown below:
[tex]Ka_{HBrO}=2x10^{-9}\\\\Ka_{HClO}=3.5x10^{-8}\\\\Ka_{HClO_2}=1.2x10^{-2}\\\\Ka_{HClO_3}>>>>1[/tex]
In such a way, since the Ka of chloric acid, HClO3 is greater than 1, we infer it is a strong acid so it is the strongest, next we have HClO2, then HClO and the weakest would be HBrO as its Ka is the smallest.
Thus, the order would be:
HClO3>HClO2>HClO>HBrO
Best regards!
Which of the following are diatomic elements? Select all that apply.
A.Hydrogen
B.Boron
C.Bromine
D.Iodine
Answer:
C
Explanation:
A diatomic element in that list is Bromine
Answer the following questions about the solubility of CoCO3(s). The value of Ksp for CoCO3(s) is 1.0 × 10^−10.
A. Calculate the value of [Co2+] in a saturated solution of CoCO3 in distilled water.
B. If 0.10 M of Co2+ is already present in distilled water, calculate the molar solubility of CoCO3(s).
C. Explain why CoCO3 is less soluble in distilled water that already contains Co2+
Answer:
Attached picture.
Explanation:
(1) Ksp equals the product of [Co 2+][CO3 2-]. CoCO3 is excluded from the equilibrium expression because it is a pure solid. The mole ratio of Co 2+ and CO3 2- is 1:1 so their molar solubilities are the same.
(2) There is an initial concentration of 0.10 M Co 2+ so write that in the "I" row for Co 2+ on the ICE table. When you find the zeros of the quadratic when solving for "s", take the positive value rather than the negative value because concentration cannot be negative.
(3) Extra products will cause the equilibrium to consume products and form reactants. So the reverse reaction will occur faster than the forward reaction. More products mean an increased Q value compared to K, since the numerator of [tex]K = \frac{[products]}{[reactants]}[/tex] increases.
Spiders create their webs on the stems and trunks of trees. The tree is unaffected by the spider web.
1.predation
2.commensalism
3.parasitism
4.mutualism
Answer:
it would be 2
Explanation:
NEED HELP ASAP
Imagine that you have a sample of a substance. You cannot physically separate that substance into components. You also cannot chemically separate that substance into components. Which of the following are true about your sample?
The sample is made up of multiple elements. t or f
The sample is made up of one type of atom. t or f
The sample is made up of several types of atoms. t or f
The sample is made up of a single element. t or f
Answer:
The sample is made up of a single element. t or f
Explanation:
Forgot about the t or f! Its true.
Dam bro.....
1. T
2. F
3. T
Answer:
i think its the 3 thired one sorry if rong but good luck
Explanation:
What frequency does a photon of wavelength 4.5 x 10-4 m have?
A. 6.67 x 1011 Hz
B. 1.47 x 10-30 Hz
C. 2.98 x 10-37 Hz
D. 1.35 x 105 Hz
SUBMIT
Answer:
6.67* 1011 Hz
Explanation:
a p e x
Answer:
Awnser above is correct
Explanation:
a. 6.67