Answer:B
Explanation:
What is the frequency of a photon whose energy is 5.4 ´ 10-19 J? (h = 6.626 ´ 10-34 J·s)
Answer:
8.15 x 10¹⁴Hz
Explanation:
Given parameters:
Energy of photon = 5.4 x 10⁻¹⁹J
h = 6.626 x 10⁻³⁴J.s
Unknown:
Frequency of the photon = ?
Solution:
The energy of a photon is given as;
E = hf
h is the Planck's constant
f is the frequency
f = [tex]\frac{E}{h}[/tex] = [tex]\frac{5.4 x 10^{-19} }{6.626 x 10^{-34} }[/tex] = 8.15 x 10¹⁴Hz
Please answer quick. In an experiment, a student collects 107 mL of H2 over water at a pressure of 104.8 kPa and a temperature of 30°C. How many grams of H2 are present?
A.
0.024 g
B.
4.00 g
C.
0.04 g
D.
0 049 g
And explain
Answer:
Mass = 0.008 g
Explanation:
Given data:
Volume of H₂ = 107 mL
Pressure = 104.8 KPa
Temperature = 30°C
Mass of H₂ present = ?
Solution:
Formula:
The given problem will be solve by using general gas equation,
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
Now we will convert the units of temperature, pressure and volume.
Temperature = 30+273 = 303 K
Volume of H₂ = 107 mL (107/1000= 0.107 L)
Pressure = 104.8 KPa (104.8/101 = 1.04 atm)
by putting values,
1.04 atm ×0.107 L = n× 0.0821 atm.L/ mol.K × 303 K
0.11 atm.L = n×24.87 atm.L/ mol
n = 0.11 atm.L / 24.87 atm.L/ mol
n = 0.004
Mass of H₂:
Mass = number of moles × molar mass
Mass = 0.004 mol × 2 g/mol
Mass = 0.008 g
The acceleration due to gravity on Earth’s moon is about 1.6m/s2. An astronaut with full survival pack has a mass of 100kg. He lifts a large boulder (rock) having a mass of 50kg. Losing his balance, and letting go of the boulder, the explorer trips and falls off a ledge that is 2m above the moon’s surface. Assuming that both the astronaut and the rock are the same distance from the surface of the moon, which object will hit the ground first:the astronaut or the rock? Explain your answer.
Answer:
Astronaut
Explanation:
Astronaut.He is 100kgs
How many neutrons does Ruthenium have?
Answer: 57 neutrons
Explanation: Ruthenium has an atomic number of 44, meaning it has 44 electrons, 44 protons, and 57 neutrons.
Answer:
57 neutrons
Explanation:
Ruthenium has atomic number of 44, that is, it contains 44 electrons distributed in atomic orbitals and its nucleus has 44 protons and 57 neutrons (Figure 1). Electron distribution in atomic or molecular orbitals is called electron configuration which for Ru and the other group 8 chemical elements is shown in Table 1.
ILL GIVE BRAINLIST Mrs. Kucalaba downloaded some science music from the Internet onto her iPhone. She listened to the science music while she was building a deck in her mom’s yard.
Which energy transformation explains how Mrs. Kucalaba was able to listen to music on her iPhone while building a deck in her mom’s yard?
Question 19 options:
Light energy was transformed to chemical energy
Chemical energy was transformed to sound energy
Sound energy was transformed to chemical energy
Chemical energy was transformed to heat energy
Help please I'll give u brainliest
What is the balanced equation that represents this reaction. sulphur trioxide reacts with water vapour in the atmosphere to form sulphuric acid (h2so4).
so3 +h2o =h2so4
i just searched up google i have no explanation
There are 5.0g of I-131 left after 40 days. How many grams were in the original sample if the half-life is 8 days?
160 grams of I-131 were in the original sample if the half-life is 8 days.
What do you mean by half life?In a chemical reaction, the time taken for the concentration of that substance to become half of its initial value is called half-life. This term is used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay .
The amount left N after n half lives of a radioactive element with original amount N₀ is given as:
N= N₀ (1/2)ⁿ
Given, half life of Iodine-131 is 8 days
n= 40/8= 5
5= N₀ (1/2)⁵
N= 32 * 5
= 160 grams
Hence, the original amount amount of I-131 will be 160 grams.
To know more about half life, refer
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Examine the diagram of a cell.
Which organelle is marked with an X?
lysosome
nucleus
chloroplast
vacuole
Answer:
chloroplast
Explanation:
i took the test
If an atom gains one electron, what charge will it have?
Answer:
It becomes negatively charged
Proton is positive, electron is negative and neutron is neutral
Explanation:
Answer:
If an atom gains one electron, it will have a negative one charge, or -1.
Electrons = Negative
Protons = Positive
which molecules are used to produce energy
Answer:
Explanation:
fats, proteins, and carbohydrates
What causes the greenhouse effect?
Answer:
hope it helps...
Explanation:
The greenhouse effect is caused by the atmospheric accumulation of gases such as carbon dioxide and methane, which contain some of the heat emitted from Earth's surface. The atmosphere allows most of the visible light from the Sun to pass through and reach Earth's surface.
Greenhouse effect is caused by the presence of greenhouse gases in the atmosphere and the trapping of energy within the lower atmosphere.
Greenhouse gases can be defined as the gases that trap heat within the Earth's atmosphere. Some examples of greenhouse gases present in the atmosphere are:
Carbon dioxideMethaneWater vaporOn a related note, greenhouse effect refers a terminology that is used to describe the role that greenhouse gases play in keeping the temperature of planet Earth warm.
In conclusion, greenhouse effect is typically caused by the presence of greenhouse gases in the atmosphere and the trapping of energy within the lower atmosphere.
Find more information: https://brainly.com/question/1577730
A given sample of metal has a density of 2.5 g/cm3 and a mass of 12.5 g. What is the
volume of the metal?
31.25 cm^3
5.0 cm^3
0.20 cm^3
5.0 cm
Answer:
5.0 cm³Explanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\ [/tex]
From the question we have
[tex]volume = \frac{12.5}{2.5} \\ [/tex]
We have the final answer as
5 cm³Hope this helps you
When 38.1 grams of a certain metal at a temperature of 90.0°C is added to 100.0mL of water at a temperature of 17.6°C in a perfectly insulated calorimeter, the final temperature of the resulting mixture is 19.1°C. a. Find the value of q for the metal b. Find the value of q for the water c. What is the specific heat of the metal?
Answer:
a. qm = 627.3 J
b. qw = 627.3 J
c. C₂ = 227.4 J/kg.°C
Explanation:
a.
Since, the calorimeter is completely insulated. Therefore,
Heat Lost by Metal = Heat Gained by water
qm = qw
qm = m₁C₁ΔT₁
where,
qm = heat lost by metal = ?
m₁ = mass of water = (density)(volume) = (1000 kg/m³)(100 mL)(10⁻⁶ m³/1 mL)
m₁ = 0.1 kg
C₁ = specific heat capacity of water = 4182 J/kg.°C
ΔT₁ = Change in Temperature of Water = 19.1°C - 17.6°C = 1.5°C
Therefore,
qm = (0.1 kg)(4182 J/kg.°C)(1.5°C)
qm = 627.3 J
b.
Since,
qm = qw
qw = 627.3 J
c.
qm = m₂C₂ΔT₂
where,
m₂ = mass of metal = 38.1 g = 0.0381 kg
C₂ = specific heat capacity of metal = ?
ΔT₂ = Change in Temperature of metal = 90°C - 17.6°C = 72.4°C
Therefore,
627.3 J = (0.0381 kg)(C₂)(72.4°C)
(627.3 J)/(0.0381 kg)(72.4°C) = C₂
C₂ = 227.4 J/kg.°C
Shameeka is studying for an exam. She took the notes below about calcium and chlorine, which are known to form ionic bonds. Calcium, which is a metal, donates 2 electrons to chlorine. The individual calcium atoms become ions with a negative 2 charge. The bond between calcium and chlorine makes the atoms stable. Calcium and chlorine attract each other. Which best describes Shameeka’s error? ive got 2 hours so you dont need to rush
Answer:
Calcium has a charge of positive 2 not negative
Explanation:
what color does red represent in the periodic table
Answer:
Gas
Explanation:
Legend primordial element element by radioactive decay Atomic number color: red=gas
Does recycling plastic solve the issue of using crude oil?
Answer:
Every single tonne of recycled plastic cuts carbon emissions by 1.6t and preserves 2t of crude oil. And each tonne that is recycled is not just one tonne less which the industry has to buy as crude oil on the global market – it is also one tonne less of waste plastic in our seas and oceans.
Earth's land areas, oceans and atmosphere maintain fairly constant average temperatures. What is the best explanation for these constant average temperatures? (8.10 A) Earth's Northern and Southern hemispheres have opposite seasons. Earth's Northern and Southern hemispheres have opposite seasons. Earth is tilted and rotates daily on its axis. Earth is tilted and rotates daily on its axis. The continuous motion of air and water distributes the sun's energy. The continuous motion of air and water distributes the sun's energy. Global weather systems generally move from west to east.
Answer:
The continuous motion of air and water distributes the sun's energy.
Explanation:
The continuous motion air and water helps to distribute the sun's energy throughout the earth, and thus maintain fairly constant average temperatures.
The equatorial regions of the earth receives more heat than regions of higher latitudes. By means of convection air currents, whereby hotter and lighter air from the equatorial regions is circulated for colder and denser air from the regions of higher latitudes, heat is distributed between these regions.
Also, the heat of surface waters at the equatorial regions is circulated in convection currents as seas and oceans move around, to other regions of the earth in order to maintain a fairly constant average temperature.
Answer:
the continuous motion of air and water distributes the suns energy.
Explanation:
plz help me its the last question
If an atom of Thulium, Tm, has a mass of 172 and ejects an alpha particle, what is the new mass and atomic number? What element does this atom belong to now?
Answer:
¹⁶⁸₇₉Au
Explanation:
The symbol of the atom is given as;
¹⁷²₈₁Tl
If undergoes a nuclear reaction and it ejects an alpha particle;
An alpha particle is the same as an helium atom
¹⁷²₈₁Tl → ₂⁴H + ₐᵇK
K is the hypothetical symbol of the new atom
b is the new mass number
a is the new atomic number;
Conserving mass number;
172 = 4 + b
b = 172 - 4 = 168
Conserving atomic number;
81 = 2 + a
81 - 2 = a
a = 79
The new compound is gold with a symbol of;
¹⁶⁸₇₉Au
The average monthly temperatures for January, April, July, and October in Baltimore, Maryland are graphed below. These averages were calculated from 30 years of data.
Nina predicts that the average temperature in Baltimore will be 68°F next April. Why is her prediction probably wrong?
A.
because the average July temperature is greater than 75°F
B.
because 68°F is much lower than the average April temperature
C.
because 53°F is much lower than the average April temperature
D.
because 68°F is much higher than the average April temperature
Answer:the answer is d
Explanation:because the graph shows that that the average temperature is 53 so it only makes sense that the answer is (D)
what is Very small and located on ER or located
floating on its own in the cytoplasm, it is
responsible for making proteins for repair and
growth.
Using your knowledge of symbols, determine which compound listed must contain both copper and oxygen.
1. malachite, Cu 2CO 3(OH) 2
2. calcite, CaCO 3
3. glucose, C 6H 12O 6
4. chalcopyrite, CuFeS 2
Answer:
Malachite
Explanation:
Malachite is the only listed compound that must contain copper and oxygen.
Copper and oxygen are both elements found on the periodic table. They have the following symbols;
Copper = Cu
Oxygen = O
From the given choices, only option 1 has the symbol Cu and O.
So only malachite contains both copper and oxygen.
Shabnam put something in a vessel of water and heated it on a gas stove for 30 minutes. That thing looked the SAME even after 30 minutes of heating. What could she have put into the vessel? A) a steel spoon B) a wax candle C) a handful of sugar D) a piece of chocolate
Answer: She could have put a steel spoon into the vessel. The correct option is A.
Explanation:
When a candle wax is passed through heat, it is capable of melting within 10- 15 minutes of boiling. Therefore it is not capable of looking the same after 30 mins of heating.
When sugar is put into water it dissolves. When heated it has the ability to crystallize out after water is evaporated but doesn't retain its shape.
A piece of chocolate will melt the instance it comes in contact with any form of heat.
A steel spoon is an alloy metal which is not capable of melting by boiling in water for just 30 minutes. A steel is an alloy of Iron and carbon which melts when superheated at the temperature of 1510 degrees.
what type of mixture is table salt
Answer:
The chemical mixture of table salt is NaCl.
Can somebody please help with this question?
What can be represented on paper or computer by using the Lewis Dot structure?
A. the electrons orbital
B. the position of an element in the periodic table
C. the valence electron shells of atoms
D. the number of total electrons
Answer:
option C is correct
Explanation:
Help me plzz I don’t get this question
Answer: this ones old do you still need help on this one?
Explanation:
The____of an earthquake is the location where the rupture of an
earthquake begins and energy is released.
(I’m really slow I need help) for science
Answer:
try hypocenter for the blank spot... hope this helps
Explanation:
How do the scientist know that cells exist
How many total atoms found in 2AClCl3
Answer: 4 atoms.
Explanation:
PLS HURRYY ILL NAME YOU BRAINLIESTTT
explain the difference between a compound and a mixture
Answer:Compound: A substance that is made up of more than one type of atom bonded together. Mixture: A combination of two or more elements or compounds that have not reacted to bond together; each part in the mixture retains its own properties. Compound are substances which can be formed by chemically combining two or more elements. Mixtures are substances that are formed by physically mixing two or more substances. Compounds can be of three types, which are: covalent compounds, metallic compounds and ionic compounds.