Answer:
1.3 moles
Explanation:
pv = nrt
n = pv/rt
n = (125 * 25) / (8.3144598 * 289)
n = 1.3 moles
Which of the following are elements in this equation: 2H2O2 (aq) → 2H2O (l) + O2 (g)?
Check all that apply:
A. O
B. g
C. Aq
D. H
draw the structure of ethoxyethane
Answer:
i couldnt draw it but here is a picture
Explanation:
How could renewable energy sources be used to heat and cool a house?
1:Which example is not a physical change?
2: Which of the following is not a clue that a chemical reaction is taking place?
Would a burning candle have potential or kinetic energy?
Answer:
When the candle is lit and burning, it has kinetic energy.
Explanation:
please smash brainliest on my doorstep
5. If 4 moles of nitrogen gas reacts with excess hydrogen gas, how many moles of NH3 will be produced?
Be sure to balance the equation first.
__N2 + __ H2 → __ NH3
a. 8 moles NH3
b. 4 moles NH3
C. 2 moles NH3
d. 12 moles NH3
What is a magnet?(2 points)
O A tool used to help determine if certain materials are magnetic
O A tool used to help determine if certain materials have a large mass
O A tool used to help determine if materials are the color blue
O A tool used to help determine if materials use the force of gravity
Place these elements in order of increasing ionization energy and JUSTIFY A REASON FOR THIS TREND. C Ge Pb Si Sn
Answer: The given elements are arranged in order of increasing ionization energy as Pb < Sn < Ge < Si < C.
Explanation:
The amount of energy required to remove a loosely bound electron from an isolated neutral gaseous atom is called ionization energy.
Larger is the size of an atom more easily it will lose its valence electrons. Hence, less will its ionization energy.
Whereas smaller is the size of an atom more energy will be required to pull out the electron. Hence, more will be its ionization energy.
This means that on moving down a group ionization energy decreases and on moving along a period from left to right the ionization energy decreases.
The given elements are C, Ge, Pb, Si, and Sn. All these elements belong to group 14 of the periodic table.
Therefore, these elements are arranged in order of increasing ionization energy as follows.
Pb < Sn < Ge < Si < C
Thus, we can conclude that given elements are arranged in order of increasing ionization energy as Pb < Sn < Ge < Si < C.
Chemistry explaining the vapour pressure
Answer:
Vapor pressure is defined as the pressure exerted by a vapor in thermodynamic equilibrium with its condensed phases (solid or liquid) at a given temperature in a closed system.
Explanation:
I need to know the answer asap
1. Molecules are held together by:
a, ionic bonds
b. covalent bonds
c. both a and b
A: ionic bond, you know why becasue it is
Uranium-235 decays to form lead-207. The half-life of uranium-235 is 704,000,000 years. What is the approximate age of an igneous rock with a 1:1 ratio of uranium-235 atoms to lead-207 atoms?
Answer:
The approximate age of the igneous rock is [tex]7.042\times 10^{6}[/tex] years.
Explanation:
Chemically speaking, the Uranium-235 decays to form Lead-207 throughout time. All isotopes decay exponentially by means of the following model:
[tex]m(t) = m_{o}\cdot e^{-\frac{t}{\tau} }[/tex] (1)
In addition, we can determine the time constant of the former isotope in terms of its half life, that is:
[tex]\tau = \frac{t_{1/2}}{\ln 2}[/tex] (2)
Where:
[tex]m_{o}[/tex] - Initial mass of Uranium-235, in atoms.
[tex]m(t)[/tex] - Current mass of Uranium-235, in atoms.
[tex]\tau[/tex] - TIme constant, in years.
[tex]t_{1/2}[/tex] - Half-life of Uranium-235, in years.
Please remind that a 1 : 1 ratio of Uranium-235 to Lead-207 atoms means that current mass of Uranium-235 is a half of its initial mass. If we know that [tex]m(t) = 0.5\cdot m_{o}[/tex] and [tex]t_{1/2} = 7.04\times 10^{8}\,yr[/tex], then the approximate age of the igneous rock is:
[tex]\tau = \frac{7.04\times 10^{8}\,yr}{\ln 2}[/tex]
[tex]\tau \approx 1.016\times 10^{9}\,yr[/tex]
[tex]t = -\tau \cdot \ln \left(\frac{m(t)}{m_{o}} \right)[/tex]
[tex]t = -(1.016\times 10^{9}\,yr)\cdot \ln \frac{1}{2}[/tex]
[tex]t \approx 7.042\times 10^{6}\,yr[/tex]
The approximate age of the igneous rock is [tex]7.042\times 10^{6}[/tex] years.
The force needed to overcome the attraction among molecules at the surface of a liquid is called?
Answer:
The type of force is known as cohesive force
What is one element that is not found in the human body, air, or the universe ?
Explanation:
For the moment we have analyzed the physical point of view. For many, the most common way to analyze your body is through the chemical elements.
This increases the number of building blocks to more than four particles, but considering that the number of atoms in a 70 kilogram body is 7,000 quadrillion (you write a 7 followed by 27 zeros), it is still quite simple that we can count the 99.95% of your body weight with only seven elements.
The provocative alternative theories to the Big Bang that state that the universe has no limits
You may have heard that most of our body is water. It may seem unlikely given how solid our bodies feel, but most of you are made of cells filled with water.
There is enough structure that you are unlikely to slide down the drain, but you do have a lot of water. About 60 percent of your body is water, even your bones are roughly 30% water.
Two skeletons sitting on the beach.
IMAGE SOURCE, GETTY IMAGES
Caption,
The bones have 30% water in their composition.
Knowing that water is made up of hydrogen and oxygen (H2O), it seems clear to point out that the elements most present in the body are hydrogen and oxygen.
But there is also much of the most versatile of atoms, carbon. All life we know incorporates water and is based on carbon structures.
Since carbon atoms weigh 12 times more than hydrogen atoms, carbon ranks second by weight behind oxygen.
The thing would be like this: we have 65% oxygen, 18% carbon and 10.2% hydrogen.
If we add a small amount of nitrogen (3.1%), a pinch of calcium for those bones (1.6%), 1.2% of phosphorus, 0.25% of potassium and sulfur and smaller percentages of sodium, magnesium and chlorine, we already reached 99.95
Aluminum chloride, AlCl3, is an inexpensive reagent used in many industrial processes. It is made by treating scrap aluminum with chlorine according to the following equation. Please balance the equation.
__2_ Al (s) + 3___ Cl2(g) _2___ AlCl3(s)
If you start with 3.11 g of Al and 5.32 g of Cl2, which reagent is limiting? How many grams of AlCl3 can be produced? During an experiment you obtained 5.57 g of AlCl3, what was your percent yield?
Answer:
Cl₂ the limiting reactant.
6.67g of AlCl₃ can be produced.
83.5% is percent yield
Explanation:
Based on the reaction:
2 Al + 3Cl₂ → 2AlCl₃
2 moles of aluminium react with 3 moles of chlorine.
To solve this question we must find the moles of each reactant in order to find limiting reactant. With limiting reactant we can find theoretical yield. Percent yield is:
Actual yield (5.57g) / Theoretical yield * 100
That means if we find theoretical yield we can find percent yield:
Moles Aluminium: 26.98g/mol
3.11g * (1mol / 26.98g) = 0.115 moles Al
Moles Chlorine: 70.90g/mol
5.32g * (1mol / 70.90g) = 0.075 moles Cl₂
For a complete reaction of 0.075 moles of Cl₂ are required:
0.075 moles Cl₂ * (2mol Al / 3mol Cl₂) = 0.050 moles of Al
As there are 0.115 moles of Al, Aluminium is the excess reactant and Cl₂ the limiting reactant.
Moles AlCl₃ and mass: 133.34g/mol
0.075 moles Cl₂ * (2mol AlCl₃ / 3mol Cl₂) = 0.050 moles of AlCl₃
0.050 moles of AlCl₃ * (133.34g / mol) =
6.67g of AlCl₃ can be producedPercent yield:
5.57g / 6.67g * 100 =
83.5% is percent yieldPlz answer fast Name the four parts of a circuit.
Answer:
A switch
Battery or cell
Resistor
Rheostat
Appliance or load such as bulb
connecting wires.
Jockey
Inductor
Capacitor
Meter bridge
Potentiometer
Voltimeter
Ammeter
Galvanometer
Which type of molecule is shown below? I CH3 C=C H CH3 O A. Alkene O B. Cyclic alkane O C. Alkane O D. Alkyne
Answer:
Alkene
Explanation:
Took the test.
The correct answer is Option (A) Alkene.
What is Alkene?Alkenes are the hydrocarbon which contain double bond of carbon and carbon.The general formula of alkene are CnH2n.Alkenes are unsaturated hydrocarbons. Why other options are incorrect?The other options are incorrect because the structure given in the question is C4H8. The IUPAC name of the structure is is 1- butene .The structure describes the general formula of alkene CnH2n where we can say that n= 4Hence , Option (A) is correct and rest options are incorrect.Learn more about Alkenes below
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A gas occupies 40.0 mL at 150 K. What volume does it occupy at 300 K,
assuming pressure is constant? *
Answer:
.08 L or 80 ml
Explanation:
Use the equation V/t = V/t.
.04L / 150K = V / 300K
.04 / 150 * 300 = V
.08 L or 80 ml
The warming of our atmosphere is due to contain gases like carbon dioxide and water vapor called greenhouse gases that insulate (trap heat) Earth. What would happen to Earth without these greenhouse gases?
Answer:
the earth would be covered in ice and we would not be able to survive as there is not natural insulation
Which of these metals reacts more vigorously with water?
1. Zinc
2. Magnesium
Answer:
magnesium
Explanation:
because zinc does not react with water because it too forms a protective layer of insoluble.
What is indicated by the prop- prefix?
Answer:
The molecule has 3 carbon atoms.
Explanation:
NaOH dissociation equation
Answer:
This can be represented by the chemical equation: NaOH H2O→ OH- + Na.
What is the name of the process scientists use to give different names to different organisms?
astronomy
economy
identification
taxonom
Answer:
D). Taxonomy.
Explanation:
'Taxonomy' is described as the process or the science of finding, describing, classifying, and naming different organisms. It is characterized as the technique of classification of animals, micro-organisms, plants, etc. into different categories or hierarchies. It has primarily been divided into eight distinct types like kingdom, species, order, family, etc.
Astronomy is associated with the study of the physical universe while the economy is defined as the study of efficient utilization of resources and identification is the process of recognizing an object. Thus, option D is the correct answer.
Which of the following is a true statement regarding living organisms? All living things- (A. Require oxygen to breath)
(B. Are capable of intelligent thought)
(C.are made up of one or more cells)
(D.have a lifespan of at least on weak?
Answer:
A or C
Explanation:
Answer:
are made up of one or more cells
Explanation:
A cell is the building block of life of any organism. Therefore, an organism simply cannot exist if it has no cells
2.0 L of oxygen gas and 8.0 L of nitrogen gas at STP are mixed together. The gaseous mixture is compressed to occupy 2.0 L at 298 K. What is the pressure exerted by this mixture?
Answer:
5.5 atm
Explanation:
Step 1: Calculate the moles in 2.0 L of oxygen at STP
At STP, 1 mole of an ideal gas occupies 22.4 L.
2.0 L × 1 mol/22.4 L = 0.089 mol
Step 2: Calculate the moles in 8.0 L of nitrogen at STP
At STP, 1 mole of an ideal gas occupies 22.4 L.
8.0 L × 1 mol/22.4 L = 0.36 mol
Step 3: Calculate the total number of moles of the mixture
n = 0.089 mol + 0.36 mol = 0.45 mol
Step 4: Calculate the pressure exerted by the mixture
We will use the ideal gas equation.
P × V = n × R × T
P = n × R × T / V
P = 0.45 mol × (0.0821 atm.L/mol.K) × 298 K / 2.0 L = 5.5 atm
state two applications of simple distillation of separating mixture
Answer:
Purify drinking water of unwanted
chemicals andminerals such as salt.Hope this helps! :D
Which example of regeneration is also considered reproduction?
Explanation:
Regeneration is a type of asexual reproduction in which the organism is capable of regrowing certain body parts.
Answer: Regeneration is defined as organism's ability to regrow damaged or lost body parts. It is a type of asexual reproduction which is shown by many fully differentiated organisms. Organism such as Hydra uses regenerative cells for reproduction in the process of budding. The young Hydra gets its nourishment from the parent.
Explanation:
how much 0.100 m h2so4 are needed to make 25.0 ml of 0.00500 m solution
Answer:
3) 1.25
Explanation:
I had the same question and somehow got it right :)
The new volume will be determined by molarity and which will be 1.25 ml.
What is volume?The volume of an object is just a measurement of how much space it takes up.
What is Molarity?
The molality refers to the moles of a solute in relation to the mass of the solvent, whereas the molarity refers to the moles of a solute in based on the volume of the solution. It can be denoted by M.
The formula of Molarity is
[tex]M_{1} V_{1} =M_{2}V_{2}[/tex]
where, M is molarity and V is volume.
Calculation of volume.
It is given that,[tex]M_{1} = 0.1 M, M_{2} =0.0025 M.[/tex]
Now, puts the value of given data in molarity equation.
[tex]M_{1} V_{1} = M_{2} V_{2}[/tex]
[tex]V_{1} = M_{2} V_{2} /M_{1}[/tex]
[tex]V_{1}[/tex] = 0.005×25/0.1 = 1.25 ml
Therefore, the correct answer will be option 3.
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Find the number of grams of calcium chloride needed to prepare 500.0ml of a 4.0m solution
Answer:
222 g
Explanation:
First we convert 500.0 mL to L:
500.0 mL / 1000 = 0.500 LThen we use the definition of molarity to calculate how many calcium chloride moles are required:
Molarity = moles / litersMolarity * liters = moles4.0 M * 0.500 L = 2.00 molNow we convert 2.00 moles of calcium chloride into grams, using its molar mass:
2.00 mol * 111 g/mol = 222 gIn completing a Fischer Esterification experiment using acetic acid and unknown alcohol catalyzed by sulfuric acid a student starts with excess acetic acid with the intention of shifting the equilibrium towards formation of product. Identify the law used to predict this effect.
Answer:
The equilibrium law
Explanation:
According to the equilibrium law , when [tex]$\text{concentration}$[/tex] of any of the reactants or the products in the reaction at an equilibrium state, is changed, then it changes the composition of equilibrium mixture in order to minimize the effect of
Acetic acid (in excess) + [tex]$\text{alcohol}$[/tex] ⇄ [tex]$\text{ester}$[/tex] + water
[tex]$\text{Fischer esterification}$[/tex] is a reaction which involves the equilibrium. So to force the reaction towards the side of [tex]$\text{ester}$[/tex], one of the reactant is taken in excess. All this can be explained easily by applying the equilibrium law.