Answer:
every 4 years we add an extra day, February 29th, to our calendars these extra days called leave days help synchronize our human created calendars with us orbit around the sun and the actual passing of our seasons
hello guys pls help me!about the importance of a chemical compound !pls i need five point
Answer:
Chemical structure determines the molecular geometry of a compound by portraying the spatial arrangement of atoms and chemical bonds in the molecule. This provides chemists with an important visual representation of a chemical formula.
How many stoms of oxygen in 4 molecules of HNO,?
Answer: the answer is a
How many carbon atoms are in 6.5 moles of carbon?
3.91 ×10²⁴ carbon atoms are in 6.5 moles of carbon. The smallest unit of matter that may be divided without producing electrically charged particles is the atom.
What is atom?The smallest unit of matter that may be divided without producing electrically charged particles is the atom. It is also the smallest piece of substance with chemical element-like characteristics. As a result, the atom serves as the fundamental unit of chemistry. Space makes up the majority of an atom.
The rest is made up of a cloud of electrons that are negatively charged surrounding a nucleus that is positively charged made up of protons and neutrons. Compared to electrons, which are the smallest charged particles in nature, the nucleus is small and dense. Electric forces, which link radicals to the nucleus of atoms, cause them to be drawn to any positive charge.
number of atoms= 6.5 × 6.022×10²³
=3.91 ×10²⁴
Therefore, 3.91 ×10²⁴ carbon atoms are in 6.5 moles of carbon.
To know more about atom, here:
https://brainly.com/question/29712157
#SPJ2
List 2 ways that the increase in human population has had a negative impact on
the environment.
I
sdfsdfsdfsfsdfsdfdfdre
Answer:
310 mmHg
Explanation:
All you have to do here in order to figure out the pressure exerted by gas
D is use Dalton's Law of Partial Pressures.
If you have 7 moles of water, how many atoms do you have?
Answer:
Explanation:
Given 7 moles H₂O
By definition, the 'mole', in chemical process, is the mass of substance (usually in grams and includes elements or molecules) that contain 6.023 x 10²³ particles (Avogadro's Number) of the given substance. The mole is also related (or, equal) to the following:
1 mole = 1 Avogadro's number of particles = 6.023 x 10²³ particles = 1 formula wt. = 1 molecular wt. = 1 gram formula weight
So, if given 7 moles of water (H₂O) => ? molecules of water (H₂O)
By the Avogadro relationship => 1 mole H₂O = 6.023 x 10²³ molecules of H₂O
Then 7 moles H₂O => 7 moles x 6.023 x 10²³ molecules H₂O/mole H₂O
= 4.216 x 10²⁴ water molecules.
_________________________________-
General FYI note ... if needed ...
The subscripts identify number of moles of element in one mole of formula weight. That is while 1 mole H₂O contains 6.023 x 10²³ molecules of water it also contains 2 moles of hydrogen or, 2 x 6.02 x 10²³ atoms of hydrogen and moles of oxygen 1 x 6.023 x 10²³ atoms of oxygen.
Which organisms in soil helps relieve element so they can be recycled
Answer:
Explanation:
Protozoa and Bacteria: Protozoa are very small one-celled creatures. They play an important role in helping to make the soil better by feeding on bacteria and releasing excess nitrogen, which is really good for plants. Bacteria are among the tiniest and most numerous organisms in the soil.
Answer: Hewo there! your answer is Below
Soil bacteria perform recycling of soil organic matter through different processes, and as a result they produce and release into the soil inorganic molecules
Explanation:
Bacteria consume organic matter and other compounds and recycle them into substances that can be used by other organisms. Bacteria can live anywhere that has water. They are more numerous, can reproduce faster and can survive harsher conditions than any other organism on Earth.
Hope this helps you!!
Have a great day❤️❤️
-August-
When determining the amount of an oxidant present by titration, you can use iodine and starch as an indicator.
First, the oxidant, like hypochlorite, oxidizes
Choose...
neutral iodine into iodide ion
iodide ion into neutral iodine
iodate polyatomic ion into iodide ion
When starch and iodine are both present, the solution is
Choose...
blue-black
brownish yellow
clear
During the titration, the titrant, like thiosulfate, reduces the
Choose...
iodide ion into iodate polyatomic ion
neutral iodine into iodide ion
iodide ion into neutral iodine
When the iodine has completely reacted at the endpoint of the titration, the solution should become
Choose...
clear
blue-black
brownish yellow
Answer:
1. iodide ion into neutral iodine
2. blue-black
3. neutral iodine into iodide ion
4. clear
Explanation:
The function of hypochlorite in iodine titration is to oxidize the iodide ion into iodine molecule as shown below;
ClO-(aq) + 2H+(aq) + 2I-(aq) ---------> 6 I2(l) + Cl- (aq)+ H2O(l)
The addition of starch to iodine leads to the formation of a starch iodide complex which has a blue black colour.
the titrant, thiosulfate, reduces neutral iodine into iodide ion as shown below;
I2 + 2S2O32- → 2I- + S4O62-
At end point, the solution becomes clear again.
Seeds, flowers, and fruits work together to help a flowering plant reproduce.
Each of these structures is made up of different kinds of tissues specialized
to perform a specific function. What level of body organization does this
group (plants, seeds, and flowers) represent?
A. Organ
B. Cell
C. Cell system
D. Body system. not B
Answer:
I think the body system
Explanation:
Answer:body system
Explanation:
4. Given that 4NH3 + 5O2 4NO + 6H2O, if 4.23 x 1022 molecules NH3 were made to react with an excess of oxygen gas, how many molecules of NO would form?
5. If 0.433 moles of sulfur react with 0.500 moles of chlorine, how many moles of disulfur dichloride are produced? Which reactant is the limiting reactant and which is the reactant in excess?
S8(l) + 4Cl2(g) 4S2Cl2(l)
6. How many grams of Fe2O3 are produced when 2.30x10^24 molecules of O2 are reacted?
7. 3.50 g of potassium reacts with water to produce potassium hydroxide and hydrogen gas. Calculate the mass of potassium hydroxide produced. The unbalanced equation is: K + H2O KOH + H2
Please help as much as possible!
Answer:
Explanation:
Given Rxn => 4NH₃ + 5O₂ => 4NO + 6H₂O
Given data => 4.23 x 10²² molecules NH₃ => ? molecules NO
Approach: Convert given value in molecules to moles, solve for moles NO by equation ratios in balanced equation. Finish by multiplying moles of NO by Avogadro's Number (= 6.02 x 10²³ molecules/mole) to obtain molecules of NO.
moles NH₃ = 4.23 x 10²² molecules NH₃ / 6.023 x 10²³ molecules/mole
= 0.0703 mole NH₃
From equation stoichiometry of balanced equation 4 moles NH₃ gives 4 moles NO. Then 0.0703 mole NH₃ => 0.0703 mole NO b/c coefficients are equal in balanced equation.
∴molecules of NO = 0.0703 mole NO x 6.03 x 10²³ molecules NO/mole NO
= 4.23 x 10²² molecules of NO.
The remaining problems can be worked much in the same way. Convert given data to moles (if not already expressed in terms of moles), apply equation ratios to calculate needed substance in moles. Finish by converting calculated moles to desired dimension.
Hints for remaining problems:
Divide given moles of reactant substances by respective coefficients, the smaller value is the limiting reactant. Work problem based on moles (not the divide value. That's just for ID of Limiting Reactant). All other reactants will be in excess.
for problem 5 ...
Given 8S(l) + 4Cl₂(g) => 4S₂Cl₂(l)
Given: 0.433mole 0.500mole
LR 0.433/8 0.500/4
= 0.054 = 0.125
Limiting Reactant => Sulfur
Work problem from given 0.433 mole sulfur. Cl₂ will be in excess on completion of rxn.
Summary:
- convert data to moles
- divide mole values calculated by respective coefficient => smaller value is limiting reactant.
- use mole ratios to determine results, NOT the divided by value <=> this is only for ID of limiting reactant.
If ya need more, put question in comments. I'll get it. Now, If you do need additional input, before I do I will ask if you followed the hint suggestions, and your calculation results. Good luck :-)
At 47c a gas has a pressure of 140kpa. The gas is cooled until the pressure decreases to 105kpa. If the volume remains constant, what will the final temperature be in kelvin’s? In degrees Celsius
Answer:
The final temperature is equal to 240 K or -33.15°C
Explanation:
Given that,
Initial temperature of the gas, T₁ = 47°C = 320 K
Initial pressure, P₁ = 140 kpa
Final pressure, P₂ = 105 kpa
We need to find the final temperature if the volume remains constant. The relation between temperature and pressure is given by :
[tex]P\propto T[/tex]
or
[tex]\dfrac{P_1}{P_2}=\dfrac{T_1}{T_2}\\\\T_2=\dfrac{P_2T_1}{P_1}\\\\T_2=\dfrac{105\times 320}{140}\\\\T_2=240\ K\\\\T_2=-33.15^{\circ} C[/tex]
So, the final temperature is equal to 240 K or -33.15°C.
The x-intercept shows us where the temperature can be no lower, defined as absolute zero. Absolute zero is 0 K. Look at the graph.
Did the line reach (0,0)? If not, how close to absolute zero was the line?
Answer:
someone please answer!:(
Answer:
No, it was 130k way from (0,0).
Explanation:
How many molecules are in 3.7 g H2O
Explanation:
Find out number of molecules first. To find out number of molecules, first we need to know the number of moles present. The number of moles can be obtained by dividing the weight by molecular mass. The Molecular mass of water is 18. Now, by multiplying the moles with the Avogadro number we can find out the number of molecules. Avogadro number is 6×(10 to the power 23). Hence the final result is 3.7/18 ×6 × ( 10 to the power 23).
Hope this helps, if not I'm very sorry.
4. Calculate the volume of ammonia gas, at s.t.p., formed from 4.28 g of ammonium
chloride
electron configuration assignment pleaseee help asappp its 100 points and I give out brainly <3
Answer:
https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Quantum_Mechanics/10%3A_Multi-electron_Atoms/Electron_Configuration
Explanation:
very small particles of solids and liquids suspended in air are called
Answer:
aerosols
Explanation:
Which of the following contains the highest number of electrons?
OA) hydroxide ion
OB) oxonium ion
C) ammonium ion
OD) oxide ion
O E) all of them contains the same number of electrons
If the empirical formula of an organic compound is CH20, then the molecular mass of the compound could be
A. 15g
B. 45g
c. 60g
D. 135g
HELP HELP HELP HELP !!!!!!
3.2 g of a gas at STP occupies a volume of 2.24 L. The gas is
Answer:
Oxygen
Explanation:
A 37.2 g sample of copper at 99.8 °C is carefully placed into an insulated container containing 188 g of water at 18.5 °C. Calculate the final temperature when thermal equilibrium is reached. Assume there is no energy transferred to or from the container. Specific heat capacities: Cu = 0.385 J g-1 °C-1 H2O = 4.184 J g-1 °C-1
Answer:
T₂ = 19.95°C
Explanation:
From the law of conservation of energy:
[tex]Heat\ Lost\ by\ Copper = Heat\ Gained\ by\ Water\\m_cC_c\Delta T_c = m_wC_w\Delta T_w[/tex]
where,
mc = mass of copper = 37.2 g
Cc = specific heat of copper = 0.385 J/g.°C
mw = mass of water = 188 g
Cw = specific heat of water = 4.184 J/g.°C
ΔTc = Change in temperature of copper = 99.8°C - T₂
ΔTw = Change in temperature of water = T₂ - 18.5°C
T₂ = Final Temperature at Equilibrium = ?
Therefore,
[tex](37.2\ g)(0.385\ J/g.^oC)(99.8\ ^oC-T_2)=(188\ g)(4.184\ J/g.^oC)(T_2-18.5\ ^oC)\\99.8\ ^oC-T_2 = \frac{(188\ g)(4.184\ J/g.^oC)}{(37.2\ g)(0.385\ J/g.^oC)}(T_2-18.5\ ^oC)\\\\99.8\ ^oC-T_2 = (54.92) (T_2-18.5\ ^oC)\\54.92T_2+T_2 = 99.8\ ^oC + 1016.02\ ^oC\\\\T_2 = \frac{1115.82\ ^oC}{55.92}[/tex]
T₂ = 19.95°C
hellppppppp asap please NO FILES
Answer:
Q1: c. 7.2 g.
Q2: a. 0.42 M.
Explanation:
Hello there!
In this case, according to the definition of molarity as moles of solute divided by volume of solution in liters, we can proceed as follows:
Q1: Here, given the molarity and volume we can calculate the moles of the sugar as follows:
[tex]n=M*V=0.4mol/L*0.1L\\\\n=0.04 mol[/tex]
Next, since its molar mass is about 180 g/mol, the mass turns out:
[tex]0.04mol*\frac{180g}{1mol} =7.2 g[/tex]
Therefore, the answer is c. 7.2 g.
Q2: Here, recalling the definition of molarity, we can just plug in the 0.629 moles and 1.500 L to obtain:
[tex]M=\frac{0.629mol}{1.5L}\\\\M=0.42M[/tex]
Therefore, the answer is a. 0.42 M.
Best regards!
Is water an acid, base, or neutral?
The number of protons in an atom is known as its atomic
Pactice 3: How is DNA changed when offspring is produced? Select all true answers.
Answer:
Asexual reproduction produces genetically identical offspring.
Binary fission is a type of asexual reproduction.
Explanation:
Asexual reproduction is that which occurs without gamete participation, ie there is no mixing of genetic material. In this process, a cell or group of them detaches from the body of a living being and gives rise to a new individual.
Individuals arising from asexual reproduction are genetically identical with each other, forming what is called a clone. These individuals will have different genetic heritage only if they undergo gene mutation, that is, alteration in the nitrogen base sequences of one or more DNA molecules.
There are several living beings that reproduce asexually among them, eukaryotes, prokaryotes, unicellular, multicellular, protists, bacteria, plants, animals, among others.
An example of asexual reproduction is binary fission, which consists of dividing a cell into two by mitosis, each with the same genome as the "mother cell" (with the same DNA or genetic material as the "mother cell").
please mark this answer as brainliest
Explain the relationship between forward and reverse
reactions at equilibrium and predict how changing the
amount of a reactant or product (creating a stress) will
affect that relationship.
For example (select one from each underlined section)
If the amount of (reactant or product) increases, the rate of the (forward or
reverse) reaction will increase or decrease) to reach a new equilibrium.
If the amount of (reactant or product) decreases, the rate of the (forward or
reverse) reaction will increase or decrease) to reach a new equilibrium.
If a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium shifts to counteract the change to reestablish equilibrium. If a chemical reaction is at equilibrium and experiences a change in pressure, temperature, or concentration of products or reactants, the equilibrium shifts in the opposite direction to offset the change. This page covers changes to the position of equilibrium due to such changes and discusses briefly why catalysts have no effect on the equilibrium position.
For example, if the system is changed in a way that increases the concentration of one of the reacting species, it must favor the reaction in which that species is consumed. In other words, if there is an increase in products, the reaction quotient, Qc, is increased, making it greater than the equilibrium constant, Kc.
A chemist needs 0.550 mol selenium for a reaction. What mass of selenium should a chemist use?
*show work and giving brainliest*
Answer:
The chemist would require to use 43.43 grams.
Explanation:
In order to solve this problem we need to know how much do 0.550 moles of selenium weigh. To do that we use selenium's molar mass and multiply it by the given number of moles:
0.550 mol * 78.96 g/mol = 43.43 gThe chemist would require to use 43.43 grams.
What are the things that is solid?
A. water
B. rock
C. oil
D. module
Answer:
The answers for these questions are B. rock and D. Module because they are both solids. The other two water and oil are liquids.
Balance the equation ___ CaCO3 -> ____ CaO + ____ CO2
Answer:
CaCO3 -> CaO + CO2
Explanation:
Woahhhh, did you balance it yourself just then?
My swimming pool is rectangular (16 feet by 34 feet) and has a depth of 6 feet. Lets imagine that my pool water is full to the top and is heated by a laser that emits photons with a wavelength of 520 nm. The starting temperature of my pool is a chilly 52 degrees Celsius. How many moles of photons would be required to heat the pool to a balmy 80 degrees Celsius
Answer:
Number of moles of photons required = 5.04 × 10⁴ moles
Explanation:
The energy of a photon can be calculated from Planck's equation E = hc/λ
Where h = 6.63 × 10-³⁴ Js and c, the velocity of light = 3.0 × 10⁸ m/s
Energy of one mole of photons = N₀ × hc/λ
wavelength of photon, λ = 520 nm = 5.20 × 10-⁷ m
Energy of one mole of photons = 6.02 × 10²³ × 6.63 × 10−³⁴ × 3 × 10⁸/5.20 × 10-⁷
Energy of one mole of photons = 2.30 × 10⁵ J/mol
Energy required to raise the temperature of a given mass of a substance, E = mcΔT
Where m is mass of substance, c is specific heat capacity, ΔT is temperature difference
Mass ofnwternin the pool = volume × density
Volume of water = Volume of swimming pool
Volume of water = 16 × 34 × 6 ft³ = 3264 ft³
1 ft³ = 28316.8 cm³; 3264 ft³ = 28316.8 × 3264 = 92426035.2 cm³
Density of water = 1 g/cm³
Mass of water = 92426035.2 cm³ × 1 g/cm³ = 92426035.2g
ΔT = 80°C - 50°C = 30°C, c = 4.18 J/g/K
Energy required to raise 92426035.2 g water by 30° C = 92426035.2 × 4.18 × 30
Energy required = 1.16 × 10¹⁰ J
Hence, number of moles of photons required = 1.16 × 10¹⁰ J/2.30 × 10⁵ J/mol
Number of moles of photons required = 5.04 × 10⁴ moles