is a salt water solution saturated when there is undissolved salt at the bottom of the bottle?
Answer:
Yes
Explanation:
What happens when this match is struck against the side of the match box?
Answer:
It lights on fire
Explanation:
The friction sparks the match causing it to go on fire.
How many molecules are in Na2CrO4
Answer:
It is 161.97324 g/mol
1 molecule
A student combines a sample of gas (2.0 L) at 3.5 atm with with another gas (1.5 L) at 2.8 atm pressure into an empty 7.0 L flask. Assuming the gases are combined at constant temperature, what is the total gas pressure (in atmospheres) in the 7.0 L flask?
Answer:
Total gas pressure is 1.60 atm
Explanation:
To solve this question we can use the Ideal Gases Law. We need to determine how many moles of each gas will be finally present at the flask of 7 L.
Let's asume the gas, are at Asbsolute T°, 273K
P. V = n . R . T
3.5 atm . 2L = n . 0.082 . 273K
(3.5 atm . 2L) / (0.082 . 273K) = 0.313 moles
(2.8 atm . 1.5L) / (0.082 . 273K) = 0.188 moles
Total moles = 0.313 mol + 0.188 mol = 0.501 mol
Let's calcualte the hole pressure
P . 7L = 0.501 moles . 0.082 . 273K
P = (0.501 moles . 0.082 . 273K) / 7L → 1.60 atm
what is the molecular geometry of c atom in ch3nh2
Answer:
compound is sp3.
Explanation:
A particular reaction has an enthalpy and entropy of reaction of ∆H = +33 kJ/mol and ∆S = +0.15 kJ/mol⋅K. At the three indicated temperatures, determine if either reactants or products are favored?
Answer:
Explanation: check my paage
What is the difference between homogeneous and heterogeneous mixtures?
I need help, due in 30 mins
Answer:
1.Reaction rate is how fast a chemical reaction proceeds.
2.Nature of the reaction, Pressure factor
, Solvent, Catalyst and inhibitors.
3.Physical change is a temporary change. A chemical change is a permanent change. A Physical change affects only physical properties i.e. shape, size, etc.
4. One example of the effect of temperature is the use of lightsticks or glowsticks.
5.When the particle size of a fixed mass of a solid reactant becomes smaller, the total exposed surface area becomes larger, the rate of reaction increases. an example could be ice and water when the atoms are stuck together a solid but all over the place as a liquid.
6. Sometimes a reaction depends on catalysts to do their job. In that case, changing the concentration of the catalyst can speed up or slow down the reaction. For example, enzymes speed up biological reactions, and their concentration affects the rate of reaction.
7.A catalyst is a chemical substance that affects the rate of a chemical reaction by altering the activation energy required for the reaction to proceed. For example, a catalyst could cause a reaction between reactants to happen at a faster rate or at a lower temperature than would be possible without the catalyst.
Explanation:
I hope this helps have a great day! :)
1. A 0.130 M solution of a weak base is titrated with a 0.130 M HCl solution. After the addition of 8.50 mL of the HCl solution to 25.00 mL of the weak base solution, the pH of the solution is 9.36 . Determine the pKb of the weak base.2. Calculate the pH of the resulting solution if 23.0 mL of 0.230 M HCl(aq) is added to (a) 33.0 mL of 0.230 M NaOH(aq).
Answer:
1. 4.93 = pKb of the weak base
2. pH = 12.61
Explanation:
1. When a weak base, B, is being titrated with HCl, the reaction occurs as follows:
B + HCl → BH⁺ + Cl⁻
That means the moles added of HCl are the moles of BH⁺ produced and moles of B are initial moles of B - Moles of HCl
Thus:
Moles B:
Initial moles:
0.0250L * (0.130mol / L) = 3.25x10⁻³ moles B
Moles HCl:
8.5x10⁻³L * (0.130mol / L) = 1.105x10⁻³ moles HCl
3.25x10⁻³ - 1.105x10⁻³ =
2.145x10⁻³ moles BMoles BH⁺ = Moles HCl:
1.105x10⁻³ moles BH⁺pH of the buffer made from B/BH⁺ is determined using H-H equation for weak bases:
pOH = pKb + log [BH⁺] / [B]
Where pOH is 14-pH = 14-9.36 = 4.64
pKb is pKb of the weak base, our unknown.
[BH⁺] could be taken as moles of BH⁺ = 1.105x10⁻³ moles
And [B] as moles of B = 2.145x10⁻³ moles B
Replacing:
pOH = pKb + log [BH⁺] / [B]
4.64 = pKb + log [1.105x10⁻³ moles] / [2.145x10⁻³ moles]
4.64 = pKb -0.288
4.93 = pKb of the weak base2. When HCl and NaOH are in solution the reaction that occurs is:
HCl + NaOH → H₂O + NaCl
To find pH we need to determine, first, which reactant is in excess:
Moles HCl:
0.023L * (0.230mol / L) = 5.29x10⁻³ moles
Moles NaOH:
0.033L * (0.0230mol / L) = 7.59x10⁻³ moles
That means NaOH is in excess and after the reaction will remain:
7.59x10⁻³ moles - 5.29x10⁻³moles = 2.3x10⁻³ moles NaOH = Moles of OH⁻
In 23+33mL = 56mL = 0.056L:
2.3x10⁻³ moles OH⁻ / 0.056L = 0.0411M [OH-]
As pOH = -log [OH-]
pOH = 1.39
pH = 14 - pOH
pH = 12.61Explain why a buffer can be prepared from a mixture of NH4CL and NaOH but not from NH3 and NaOH .
A buffer solution is often referred to as a mixture of an aqueous solution of a weak acid and its conjugate base or weak base and its conjugate acid.
NH4CL is a weak base and NaOH is a strong base and when both it gives you a basic buffer and the result will give you an acid/base needed for the buffer.NH 3 is a weak base, but NaOH is a strong base and therefore the combination of these solutes would not make a buffer solution because both will give you a base and no acid.Conclusively we can say that an acid or base needed for making buffer solutions and not base alone
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2. Find the ΔH for the reaction below, given the following reactions and subsequent ΔH
values:
2C2(g) + H2O(g) → C2H2(g) + ⁵/₂ O2(g)
C2H2(g) + 2H2(g) → C2H6(g) ΔH = –94.5 kJ
H2O(g) → H2(g) + ½ O2 (g) ΔH =71.2 kJ
C2H6(g) + ⁷/₂ O2(g) → 2 CO2(g) + 3 H2O(g) ΔH = –283 kJ
Using the two models, compare the processes of nuclear fusion and nuclear fission. What do the two processes have in common?
Choose all that apply.
A)
Energy is released.
B)
Elements are created
0)
A chain reaction occurs.
D)
Besides energy, neutrons are released.
E)
Both processes begin with an unstable nucleus.
Answer:it’s A and B
Explanation:
Answer:
A and B
Explanation:
They’re both fusion.
For at least the last century Florida has experienced a hurricane season every year, from June to November. Which of the following describes this occurrence the BEST?
A. Florida's precipitation
B. Florida's global pattern
C. Florida's climate
D. Florida's weather
Answer:
Florida's Global Pattern.
Explanation:
Because of where Florida sits, the weather in the Gulf of Mexico actually blows enough water to Create tidal waves, and also hurricanes. at least that's what I was told cause I live here :>
Help in history class please Thnks
Answer:
C) Foreign relations and war powers
Weathering is the process that takes place as rocks, and other parts of the geosphere, are??
The equation for the reaction of magnesium ribbon and hydrochloric acid is
Mg(s) + 2 HCl(aq) → MgCl2(aq) + H2(g)
If 1.53 g magnesium reacted, how many moles of hydrogen gas was produced?
Report your answer to three significant figures.
Mg = 24.3 g/mol
Answer: .063
Explanation:
1.53g Mg * (1 mol Mg/ 24.3 g Mg) * (1 mol H2/1 mol Mg) = .063 mol H2
The mole of hydrogen gas that will be produced from the reaction would be 0.0630 moles.
From the equation of the reaction:
[tex]Mg(s) + 2 HCl(aq) ---> MgCl_2(aq) + H_2(g)[/tex]
The mole ratio of Mg to H2 gas is 1:1. Thus, for every one mole of Mg consumed by the reaction, 1 mole of H2 is produced, all other things being equal.
Recall that: mole = mass/molar mass
1.53 g of magnesium = 1.53/24.3
= 0.0630 mole (to 3 significant figures)
Since the mole ratio of Mg to H2 is 1:1, it means that the number of moles of hydrogen gas produced would also be 0.0630 moles.
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what processes add methane (CH4) to the atmosphere
Answer:
Cultivated rice paddies
Drilling of natural deposits
Fossil fuel use
Burning of biomass
Landfills
Explanation:
The bulk of the methane released into the atmosphere are as a result of various human activities.
Cultivated rice paddies are a known source of methaneThe drilling of natural deposits and their exploration can release some methane into the atmosphereBurning of fossil fuel and biomass is a source of methane Landfills produces methane as organic materials begins to decay.At equilibrium, the value of [H ] in a 0.240M solution of an unknown acid is 0.00417M . Determine the degree of ionization and the Ka of this acid.
Answer:
[tex]ionization=1.74\%[/tex]
Explanation:
Hello!
In this case, since the degree of ionization of an acid is computed in terms of the concentration of hydrogen ions and the initial concentration of the acid:
[tex]ionization=\frac{[H^+]}{[HA]} *100\%[/tex]
Because the ionization reaction is represented by:
[tex]HA\rightleftharpoons H^++A^-[/tex]
Therefore, the degree or percent ionization turns out:
[tex]ionization=\frac{0.00417M}{0.240M} *100\%\\\\ionization=1.74\%[/tex]
Best regards!
How many more electrons are there in the last energy level of phosphorus, atomic
number 15, than there are in the last principal energy level of neon, atomic number 10?
sorry but I need some three point so that's why I didn't
Is adding food coloring to frosting a chemical reaction?
Answer:
no
Explanation:
Answer:
Yes
Explanation:
Adding food coloring to batter or to your icing involves a chemical reaction of the two products bonding together. This bonding process starts when you add the color and mix it in, but it doesn't end straight away as the color needs some time to fully integrate and settle.
The molarity (M) of an aqueous solution containing 22.5 g of sucrose (C12H22O11) in 35.5 mL of solution is ________.
Answer:
1.86 M
Explanation:
From the question given above, the following data were obtained:
Mass of sucrose (C12H22O11) = 22.5 g
Volume of solution = 35.5 mL
Molarity of solution =?
Next, we shall determine the number of mole in 22.5 g of sucrose (C12H22O11). This can be obtained as follow:
Mass of sucrose (C12H22O11) = 22.5 g
Molar mass of C12H22O11 = (12×12) + (22×1) + (16×11)
= 144 + 22 + 176
= 342 g/mol
Mole of C12H22O11 =?
Mole = mass /Molar mass
Mole of C12H22O11 = 22.5 /342
Mole of sucrose (C12H22O11) = 0.066 mole
Next, we shall convert 35.5 mL to litres (L). This can be obtained as follow:
1000 mL = 1 L
Therefore,
35.5 mL = 35.5 mL × 1 L / 1000 mL
35.5 mL = 0.0355 L
Thus, 35.5 mL is equivalent to 0.0355 L.
Finally, we shall determine the molarity of the solution as follow:
Mole of sucrose (C12H22O11) = 0.066 mole
Volume of solution = 0.0355 L.
Molarity of solution =?
Molarity = mole /Volume
Molarity of solution = 0.066/0.0355
Molarity of solution = 1.86 M
Therefore, the molarity of the solution is 1.86 M.
Calculate the amount of heat (in J) needed to raise the temperature of 3.50 g of water from 22.4oC to 98.8oC.
Answer:
76.4oC or 169.52oF
Explanation:
That's the amount of heat needed
The heat capacity is the heat amount lost or gained by the object in a thermodynamic system. The heat needed to raise the temperature of the water is 1117.7 Joules.
What is heat capacity?Heat capacity (q) is the heat an object loses or gains to alter the temperature of the thermodynamic system by a difference of a degree Celsius. The heat capacity is given by the mass, specific heat capacity, and temperature change.
Given,
Mass of water (m) = 3.50 gm
Specific heat (c) = 4.18 J/ g°C
The temperature change (∆T) = T₂ - T₁
= 98.8 °C - 22.4 °C
= 76.4 °C
The heat capacity is given as,
q = mc∆T
Substituting values above:
q = 3.50 gm × 4.18 J/ g °C × 76.4 °C
q = 1117.7 J
Therefore, 3.50 g of water has a heat capacity of 1117.7 Joules.
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Would you want to build the wire for a cell phone charger out of nitrogen (N)? Why or why not? Be sure to explain how the properties and structure of nitrogen influence your decision.
Answer:
No
Explanation:
Nitrogen cannot be used to build the wire for a cell phone charger.
What are the elements used to build charger ?
Inside phone chargers is aluminum. Aluminum is used in phone chargers because it does a better job of conducting electricity than copper does. Bauxite is used to make aluminum. The crust of the earth contains aluminum.A phone charger is also made of tungsten. The wire's resistance is provided by tungsten. Wolframite make up tungsten. The crust of the Earth contains tungsten.Additionally, phone chargers contain gold. Because it is a conductor, gold is used in phone chargers. However, gold is also resistant to oxidation. Copper ores are used to make gold. Gold can be found everywhere on Earth and in its oceans.Silver is within your mobile charger. Silver conducts electricity. Silver is comprised of various minerals. Silver can be found free in nature at times, but it can also be found in copper, gold, and nickel.Phone chargers contain copper. Copper is also used to carry electric current.Chalcopyrite make up copper. Copper ore deposits can be found all over the world.Copper windings in a transformer are used to convert a 220 V input voltage into a 5 V operating output voltage in mobile phone chargers. The output voltage is greater than the input voltage if the secondary coil has more turns than the primary coil.Nitrogen (N), a nonmetallic element in the periodic table's Group 15 [Va] group. It is the most abundant element in Earth's atmosphere and a component of all living matter. It is a colorless, tasteless, and odorless gas. Nitrogen is used to shield motors, prevent oxidation and other chemical reactions, pressurize cable jackets, and more in the electrical industry.To know more about Nitrogen check this:
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Of the following, which is NOT a component of the circulatory system?
A. Heart
B. Veins
ws
C. Arteries
D. Brain
Answer:
D. Brain
~PumpkinSpice1
How is thermal energy transferred during conduction? Check all that apply.
Thermal energy is transferred hetween particles that are not touching each other.
Thermal energy is transferred between particles that are in direct contact with each other.
Thermal energy is transferred between objects of different temperatures.
Thermal energy is transferred between objects of the same temperature.
Thermal energy is transferred from slow-moving particles to fast-moving particles.
Thermal energy is transferred from fast-moving particles to slow-moving particles.
Answer:energy
Explanation:needed points sorry
How many grams of CO2 are produced by the combustion of 344 g of a mixture that is 33.6% CH4 and 66.4% C3H8 by mass
Answer:
1,002.936 g
Explanation:
The combustion equation of each will be;
CH4 + 2O2 = CO2 + H2O
C3H8 + 5O2 = 3CO2 + 4H2O
We are told the mixture is 344g.
Thus;
For CH4 combustion;
Amount of CH4 = 0.336 × 344 = 115.584g
Molar mass of CH4 is 16 g/mol
Number of moles of CH4 is;
n = 115.584g/(16 g/mol)
n = 7.224 moles
n(CO2) = n(CH4) = 7.224 moles
For C3H8 combustion;
Amount of C3H8 = 0.664 × 344 = 228.416 g
Molar mass of C3H8 = 44 g/mol
Thus;
Number of moles of C3H8 = 228.416 g/(44 g/mol) = 5.19 mol
n(CO2) = 3n(C3H8) = 3 × 5.19 = 15.57 moles
Total moles of CO2 = 7.224 moles + 15.57 moles = 22.794 mol
Molar mass of CO2 = 44 g/mol
Thus amount of CO2 by mass = 22.794 mol × 44 g/mol = 1,002.936 g
For a 0.300 mol sample of helium gas in a 0.200 L container at 248K, will the pressure be greater if calculated with the ideal gas law or the van der Waals equation, and by roughly how much? (For He,a=0.0342L2atmmol2,b=0.0237 Lmol)
Answer:
It changes by roughly 1 atm.
Explanation:
Hello!
In this case, since the ideal gas equation differs from the van der Waals' one by the presence of the a and b parameters which correct the assumption of no interactions into the container, they are written as:
[tex]P=\frac{nRT}{V}\\\\P=\frac{RT}{v_m-b}-\frac{a}{v_m^2}[/tex]
Thus, the pressure via the ideal gas equation is:
[tex]P=\frac{0.300mol*0.082\frac{atm*L}{mol*K}*248K}{0.200L}=30.5atm[/tex]
And the pressure via the van der Waals equation, considering the molar volume (vm=0.200L/0.300L=0.667L/mol) is:
[tex]P=\frac{0.082\frac{atm*L}{mol*K}*248K}{0.667L/mol-0.0237L/mol}-\frac{0.0342atm*L^2/mol^2}{(0.667L/mol)^2}\\\\P=31.6atm-0.0769atm\\\\P=31.5atm[/tex]
It means that the pressure change by 1 atm, which is not a significant difference for helium.
The difference in pressure calculated by the two methods is 84 atm.
The ideal gas equation is given by
PV =nRT
From the data given in the question;
P = ?
V = 0.200 L
n = 0.300 mol
T = 248K
R = 0.082 atmLK-1Mol-1
P = nRT/V
P = 0.300 mol × 0.082 atmLK-1Mol-1 × 248K/0.200 L
P = 30.5 atm
From Van der Waals equation;
P = RT/V - b - a/V^2
P = (0.082 × 248/0.200 - 0.0237) - (0.0342/ 0.200^2)
P = 114.5 atm
The difference in pressure calculated by the two methods is;
114.5 atm - 30.5 atm = 84 atm
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Which statement describes how phase changes
can be diagrammed as a substance is heated?
The phase is on the y-axis and thew
temperature is on the x-axis.
The temperature is on the y-axis and the
phase is on the x-axis.
The time is on the y-axis and the temperature
is on the x-axis.
The temperature is on the y-axis and the time
is on the x-axis
Answer: D
Explanation:
On edge
Answer:
D
Explanation:
just did it on Ed
While setting up a beaker to boil a solution on a hot plate, you notice that the stirring is erratic and unstable. What should you do to stabilize the stirring solution? a. Clamp the beaker in place at the edge of the hot plate. b. Move the beaker to the center of the hot plate. c. Turn down the stirring speed. d. Completely turn off the stirring function.
Answer:
B. Move the beaker to the center of the hot plate
Explanation:
The erratic and unstable stirring might be caused by the beaker not being properly balanced on the hot place, there by distorting the the center of gravity of the stirring motion.
In properly positioning the stirrer to the hot plate, the magnetic rod is positioned to the center of the fluid, allowing for a more fluid and even effective stirring.
I hope this was helpful.
Please Help!!
Nitrogen gas can be prepared by passing ammonia over copper(II) oxide, and the other products are copper metal and water vapor. If a sample containing 3.58 moles of NH₃ is reacted with excess copper(II) oxide, how many grams of N₂ will be formed?
Mass of N₂ will be formed : 50.12 g
Further explanationReaction
2 NH₃(g) + 3 CuO(s) → N₂(g) + 3 Cu(s) + 3 H₂O(g)
moles NH₃ = 3.58
ratio mol NH₃ : mol N₂ = 2 : 1
so mol N₂ :
[tex]\tt \dfrac{1}{2}\times 3.58=1.79[/tex]
mass N₂ (MW=28 g/mol) :
[tex]\tt 1.79\times 28=50.12~g[/tex]