Answer:2 hours
This range of temperatures is often called the "Danger Zone." Never leave food out of refrigeration over 2 hours. If the temperature is above 90 °F, food should not be left out more than 1 hour. Keep hot food hot—at or above 140 °F.
Explanation:
In test tube 3, 3 mL of .002 M Fe(III) solution is combined with 7 mL of .02 M 5-sulfosaliclic acid (SSA) solution. What is the mole fraction of SSA in the test tube
Answer:
0.96
Explanation:
Number of moles of Fe(III) = 3/1000 * 0.002 M = 6 * 10^-6 moles
Number of moles of SSA = 7/1000 * 0.02 = 1.4 * 10^-4 moles
Total number of moles = 6 * 10^-6 moles + 1.4 * 10^-4 moles
Mole fraction of SSA = number of moles of SSA/ total number of moles.
Mole fraction of SSA = 1.4 * 10^-4 moles/ 6 * 10^-6 moles + 1.4 * 10^-4 moles
Mole fraction of SSA = 0.96
TRUE OR FALSE
Astronomers use spectroscopes to identify elements in stars because each element produces
unique emission spectrum
Answer:
True!
Explanation:
A spectrum is simply a chart or a graph that shows the intensity of light being emitted over a range of energies. Have you ever seen a spectrum before? Probably. Nature makes beautiful ones we call rainbows. Sunlight sent through raindrops is spread out to display its various colors (the different colors are just the way our eyes perceive radiation with slightly different energies).
Hope i helped!
A chef uses a large aluminum spoon with a mass of 38.0 g to stir a pot of boiling water. As a result, the spoon’s temperature increases by 3.60°C. Consider that the specific heat capacity of aluminum is 0.90 J/g–°C. How much heat has the spoon absorbed? For credit, you must show all steps of your calculations.
Answer:
12,312 J or 0.12312 kJ
Explanation:
q = mCT
q = J of heat
m = mass
C = heat capacity
T = temp change
q = 38 x 0.90 x 3.6
q = 12312 J
q = 0.12312 kJ
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Is Cu(OH)2 a covalent bond , an ionic bond or both?
The bond between the Cu²⁺ and OH⁻ ions is, well, ionic. However, the bond between the O and the H in the OH⁻ ion is covalent. So Cu(OH)₂ is, as a whole, an ionic compound, but it contains or comprises both ionic and covalent bonds.
Waves that we cannot actually see (unlike ripples in water) and that DO NOT need a medium to travel through belong to which category of waves?
Answer:
electromagnetic waves
Explanation:
The waves that do not need a medium to travel through are known as electromagnetic waves.
What are electromagnetic waves?These waves do not need any medium for their propagation or traveling. The waves have different wavelength and energy factors depending upon their rate of propagation. EMR waves travel from the sun to the earth in space.
Examples of electromagnetic waves are Xrays, gamma rays, radio waves, and more.
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Pt2 science......
Select correct answer ♡!
The equilibrium constant for the reaction shown below is Kc=0.0091. If the equilibrium concentrations of A and B are 0.031 M and 0.0823 M, respectively, what is the equilibrium concentration of C?
Answer:
[tex][C]=0.0221M[/tex]
Explanation:
Hello there!
In this case, according to the given chemical reaction at equilibrium:
[tex]3A\rightleftharpoons 3B+2C[/tex]
It is possible for us to set up the equilibrium expression as shown below:
[tex]Kc=\frac{[B]^3[C]^2}{[A]^3}[/tex]
Whereas Kc, [A] and [B] are known as 0.0091, 0.031M and 0.0823M and it is required to calculate [C]; thus, we solve for it as follows:
[tex][C]^2=\frac{[A]^3Kc}{B]^3}[/tex]
[tex][C]=\sqrt{\frac{(0.031)^3*0.0091}{(0.0823)^3}}[/tex]
[tex][C]=0.0221M[/tex]
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How is saturn like earth In any ways?
Answer:
Its axis is tilted by 26.73 degrees with respect to its orbit around the Sun, which is similar to Earth's 23.5-degree tilt. This means that, like Earth, Saturn experiences seasons. Like Jupiter, Saturn is made mostly of hydrogen and helium.
Explanation:
Thats all I could think of, please mark brainliest
Is this true or false ?
Answer:
Its true
Explanation:
Distance time graphs
50 POINTS
Gizmos Moles Activity - chemistry
can someone please help me out
there is how I would answer it.
Just a curious question to the Chemists,
If you were to 'accidentally' discover something through a chemical reaction that could change the world, what would it be and what positive impact would it have on society?
Answer:
well the world would be shocked
Explanation:
and suprise
Five liters of air at -35°C is warmed to 89°C. What is the new volume if the pressure remains constant
Answer:
7.61 liters
Explanation:
From the question,
Applying Charles law formula,
V₁/T₁ = V₂/T₂...................... Equation 1
Where P₁ = initial volume of of air, V₂ = Final volume of air, T₁ = Initial Temperature of air, T₂ = Final Temperature of air.
make V₂ the subject of the equation
V₂ = (V₁×T₂)/T₁............... Equation 2
Given: V₁ = 5 liters, T₁ -35 °C = (-35+273) K = 238 K, T₂ = 89°C = (89+273) K = 362 K
Substitute these values into equation 2
V₂ = (5×362)238
V₂ = 1810/238
V₂ = 7.61 liters
the temperature will decrease the rate of reactions.
Answer:
true?
Explanation:
kadalasang pinupuntahan ng mga patalastas
acids are and can destroy your skin and bones
Answer:
This is true.
Explanation:
In the above equation how many moles of NO can be made when 43 moles of HNO3 are consumed?
Answer:
rn4y8rg7348y0rp934nrf3
efjewhrf8h934hfr84398wgfyu8o
Explanation:
fe8u34h4n3urhu93q4pirnpqr34uwbry8439br8u3i2rpi34ofreuebue rf ef erf3rw wg
80 grams of water releases 2550 joules of heat. What is the temperature change of the water? Heat capacity of water is 4.2 J/g°C.
Answer:
7.59°C
Explanation:
Using the formula;
Q = m × c × ∆T
Where;
Q = amount of heat (joules)
m = mass of substance (g)
c = specific heat capacity (J/g°C)
∆T = change in temperature (°C)
According to this question;
m = 80g
c = 4.2 J/g°C.
Q = 2550J
∆T = ?
Using Q = m × c × ∆T
∆T = Q/mc
∆T = 2550 ÷ (80 × 4.2)
∆T = 2550 ÷ 336
∆T = 7.589°C
The change in temperature of water = 7.59°C.
what is the bond formation of N and H
Answer:
A single bond, but it's also a hydrogen bond.
Explanation:
A hydrogen bond forms when hydrogen bonds to the 3 most electronegative atoms: Oxygen, Nitrogen, or Fluorine.
It's a single bond because hydrogen only has two valence electrons. Therefore, the rest of the electrons are placed around the nitrogen atom.
10 points! Will mark brainliest!!
How does sunlight affect seasons?
Answer:
Seasons are caused by the Earth’s revolution around the Sun, as well as the tilt of the Earth on its axis. The hemisphere receiving the most direct sunlight experiences spring and summer, while the other experiences autumn and winter. During the warmer months, the Sun is higher in the sky, stays above the horizon for longer, and its rays are more direct.
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Help if possible!
Picture attached with the problems.
IS ANYONE GOOD WITH CHEMISTRY???! i need help lol
Answer:
Help with what?
Explanation:
Answer:
help with whattt
Explanation:
um
why is the sky black in space
Answer:Since there is virtually nothing in space to scatter or re-radiate the light to our eye, we see no part of the light and the sky appears to be black.
Explanation:
What is the molar mass of Fe2(CO3)3?
Answer:
291.7167
Explanation:
The molar mass of Fe₂(CO₃)₃ is 291.714 g/mol.
To calculate the molar mass of Fe₂(CO₃)₃, we need to consider the atomic masses of the individual elements present in the compound.
The molar mass of each element is as follows:
Fe (iron): 55.845 g/mol
C (carbon): 12.011 g/mol
O (oxygen): 15.999 g/mol
Now, let's calculate the molar mass of Fe₂(CO₃)₃:
Molar mass = (2 × atomic mass of Fe) + (3 × atomic mass of C) + (9 × atomic mass of O)
Molar mass = (2 × 55.845 g/mol) + (3 × 12.011 g/mol) + (9 × 15.999 g/mol)
Molar mass = 111.69 g/mol + 36.033 g/mol + 143.991 g/mol
Molar mass = 291.714 g/mol
Therefore, the molar mass of Fe₂(CO₃)₃ is approximately 291.714 g/mol.
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#SPJ 2
Would this be a strong or weak acid
Answer:
It Should be Strong Acid
Explanation:
Strong acids and bases ionize fully in an aqueous solution. Weak acids and bases also ionize, but only partially and the reaction is reversible. So how do we know if an acid or base is strong or weak? A simple way to determine strength is to add the acid or base to water— high reactivity means a stronger acid or base. This reactivity is measured with a value called the Ka or Kb value. It tells us how reactive an acid or a base is based on how many hydronium or hydroxide ions are formed during the reaction. Hope it helps :)
Which statement best describes how an existing theory is often affected by the development of new technology?
An existing theory is thrown out and replaced with a completely new theory based on the new observations.
An existing theory is modified so that it can explain both the old and new observations.
An existing theory remains the same because a theory is a proven fact that is always true.
An existing theory is kept unchanged while a new theory is developed to explain the new observations.
Answer: An existing theory is modified so that it can explain both the old and new observations.
Explanation:
Answer:
The correct anwser would be B
Explanation:
Pablo wants to enter the science fair. Which question could be answered through scientific investigation?
Answer:
Hello
Explanation:
utd847dcpyc08td0
PLEASE HELP AND FAST!! How many grams of NH4OH are in 0.125L of a 1.4 M solution of NH4OH?
Answer:
6.132
Explanation:
How much water must be added to 40.0 g of CaCl2 to produce a solution that is 35.0 wt% CaCl2?
The mass of water present in the solution is 21.5 g.
What is concentration?Concentration refers to the amount of solute in a solution. There are various ways of expressing concentration such as;
Molar concentrationMass concentrationPercentage concentrationWe have the following information;
Percent concentration = 35.0 %
mass of solute = 40.0 g
Mass of water = ?
So;
35 = x/40 + x × 100/1
35 = 100x/40 + x
35(40 + x) = 100x
1400 + 35x = 100x
1400 = 100x - 35x
1400 = 65x
x = 1400/65
x = 21.5 g
Hence the mass of water is 21.5 g.
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