Answer:
O Trilobites
Explanation:
The first mass extinction that occurred between the Paleozoic and the Mesozoic era caused the extinction of the trilobites.
Extinction are catastrophic events that causes the loss of organisms on the earth surface. Several factors can lead to extinction.
The first mass extinction took place between the Paleozoic and the Mesozoic era. This wiped out one of the most successful organism on the earth surface at that time. They were the trilobites.how many moles of sodium are present in a sample of sodium having a mass of 137 g? (molar mass is 23.0g)
Answer:
5.95 moles
Explanation:
No of moles = given mass / molar mass
No of moles = 137/23
= 5.95 moles
The Atomic mass if hydrogen us 1.008 amu. The reason that this value is not a whole number is that
A. The Mass of hydrogen is the sum of the masses of the protons and electrons in the atom
B. Hydrogen has more than one isotope
C. Hydrogen only exists as a diatomic molecule
D. The Mass of a proton is not exactly equal to 1 amu
Answer:
I'm pretty sure its c
Explanation:
The atomic mass of hydrogen, which is 1.008 amu, is not a whole number because hydrogen has more than one isotope.
The atomic mass of an element is got from the sum of the proton and neutron in its atom. However, the atoms of some element exists in more than one isotope. Isotopes are atoms of the same element with same atomic number but different atomic masses. The different atomic masses arise from the difference in the number of neutrons of each isotope. Hydrogen has more than one isotope. The atomic mass of an element with more than one isotope is the weighted average of the mass numbers of the different isotopes of that element, hence, the resulting value cannot be a whole number.Learn more at: https://brainly.com/question/11680817?referrer=searchResults
When a substance has large or strongly-attracted particles, they do not flow freely. For example, water flows very quickly compared to honey. Which property of liquids does this example illustrate?
Answer:
Viscosity
Explanation:
Viscosity is how thick a liquid is due to internal friction.
Which most likely represents the process of dissolving carbon dioxide in soda?
increased temperature to increase solubility
increased pressure to increase solubility
decreased agitation to decrease solubility
decreased pressure to increase solubility
Answer:
its increased pressure to increase solubility
Answer:
B
Explanation:
i took the quiz
What is the percent composition of nitrogen in N 2 O
Answer:
28 %
Explanation:
Mass mass N2O = 28 + 16 = 44 mass nitrogen = 2 x 14 = 28 % nitrogen Chemistry.
A car takes 4 hours to cover a distance, if it travels a speed of 40 mph. What should be it's speed to cover the same distance in 1.5 hours?
a sample of carbon dioxide gas at a pressure of 1.10 atm and a temperature of 20.6 occupies a volume of 19.2 L. If the gas is allowed to expand at constant temperature to a volume of 24.3 L, the pressure of the gas sample will be ________ atm
Answer:
0.87atm
Explanation:
Given parameters:
Pressure of the gas = 1.1atm
Initial temperature = 20.6°C = 20.6 + 273 = 293.6K
Initial volume = 19.2L
New volume = 24.3L
Unknown:
New pressure = ?
Solution:
To solve this problem, we apply the Boyle's law equation:
P1V1 = P2V2
P and V are pressure and volume
1 and 2 are the initial and new states
1.1 x 19.2 = P2 x 24.3
P2 = 0.87atm
If 15.7 grams of A1203 are produced, how many grams of iron (Fe) were
produced?
2 Al(s) + 3 FeO(s) → 3 Fe(s) + Al2O3(
An unknown atom has 5
protons, 7 electrons and 12
neutrons.
What is........
A. The atomic mass =
Answer:
17
Explanation:
the atomic mass is away protons + neutrons, electrons are neglatable.
HELP! I will mark you as Brainliest
How does the energy of a wave relate to the wave’s amplitude?
The more energy a wave has, the smaller the amplitude is. This is because they do not have a direct relationship.
The more energy a wave has, the larger the amplitude is. This is because they do not have a direct relationship.
The more energy a wave has, the smaller the amplitude is. This is because they have a direct relationship.
The more energy a wave has, the larger the amplitude is. This is because they have a direct relationship.
Answer:
They have direct relationship and larger wave energy.
Answer:
Its D on edge
Explanation:
i took the test
how many oxygen atoms are in 10.0g of 2Al2 CO3 3
Answer:
0.776 ×10²³ atoms of oxygen
Explanation:
Given data:
Mass of Al₂CO₃ = 10.0 g
Number of atoms of oxygen = ?
Solution:
Number of moles of Al₂CO₃:
Number of moles = mass/molar mass
Number of moles = 10.0 g/233.99 g/mol
Number of moles = 0.043 mol
1 mole of Al₂CO₃ contain 3 mole of oxygen.
0.043 ×3 mol = 0.129 mol
Number of atoms of oxygen:
1 mole contain 6.022×10²³ atoms
0.129 mol × 6.022×10²³ atoms / 1mol
0.776 ×10²³ atoms of oxygen
Volcanic islands can form over hot spots. The Hawaiian Islands started forming over hot spots in the Pacific Ocean millions of years ago. What process causes the hot, solid rock to rise through the mantle at these locations?
Answer: Convection Currents
Explanation:
Due to the different temperature occurring at the upper and lower layers of the mantle, it causes heat transfer to occur. One of such heat transfer is the Convection currents which causes warmer, less dense rock material in the core to rise through the mantle. Also, the cooler rocks in the higher mantle move slowly towards the core.The movement caused by these Convection current in the Earth are called plate tectonics which are responsible for earthquakes and volcanoes.
What are the half-reactions for a galvanic cell with aluminum and gold
electrodes?
Answer:
A
Explanation:
In a galvanic cell, energy is produced by spontaneous chemical processes.
The cathode and anode of this cell will depend on the relative position of the two metals in the electrochemical series.
Aluminium is higher in the electrochemical series so aluminium will be the anode. Silver is lower in the electrochemical series so silver will be the cathode.
Recall that oxidation (electron loss) occurs at the anode while reduction (electron gain) occurs at the cathode.
The half-reactions for the galvanic cell with aluminum and gold electrodes is [tex]\mathbf{Al_{(s)}\to Al^{3+} _{(aq) } + 3e^- \ and \ Au^+_{(aq)} +e^- \to Au_{(s)}}[/tex]
Galvanic cells are electrochemical cells that generate electrical energy by the spontaneous activity in the oxidation-reduction (redox) reaction process.
The position of the metals if they are going to be at the cathode or at the anode relatively depends on the position with which they find themselves in the electrochemical series. The higher metal will be the anode and the lower metal in the electrochemical series will be the cathode.
Since aluminum is higher than gold on the electrochemical series, then:
Aluminum = anode (oxidation of aluminum from solid to aqueous state)Gold = cathode (reduction of gold from aqueous to solid-state)Therefore, the half-reactions for the galvanic cell with aluminum and gold electrodes is [tex]\mathbf{Al_{(s)}\to Al^{3+} _{(aq) } + 3e^- \ and \ Au^+_{(aq)} +e^- \to Au_{(s)}}[/tex]
Learn more about Galvanic cells here:
https://brainly.com/question/25606597
13. What is the charge of an aluminum ion that has 13 protons and 10 electrons?
Answer:
+ 3
Ex planation:
Al3+ indicates an ion of aluminum having a charge of + 3. I.e., since an aluminum atom normally has 13 protons and 13 electrons, this ion has 10 electrons (-10 charge) and 13 protons (+ 13 charge) giving it a charge of + 3 (-10 + 13 = +3).
hope this helps!
Question 1 of 10
How is the energy of an electromagnetic wave carried from one place to
another?
A. By moving with the particles of the medium
O B. Through compression waves
O c. Through interactions with waves of different frequencies
O D. In changing electric and magnetic fields
Is luster a chemical or physical change? (Worth 50 POINTS!)
Answer:
It is a Physical change, have a great day :)
Explanation:
A chemical change is a permanent change. A Physical change affects only physical properties i.e. shape, size, etc. ... Some examples of physical change are freezing of water, melting of wax, boiling of water, etc. A few examples of chemical change are digestion of food, burning of coal, rusting, etc.
2. Convert 120.02g of FrBiz to moles
a. 0.19 moles
b. 5.34 moles
c. 76,932.82 moles
Answer:
PRACTICE MULTIPLE CHOICE QUESTIONS FROM UNIT 10
1.) A cylinder is filled with 2.00 moles of nitrogen, 3.00 moles of argon, and 5.00 moles of helium. If
the gas mixture is at STP, what is the partial pressure of the argon?
(A) 152 torr (B) 228 torr (C) 380. torr (D) 760. torr
2.) Compared to the average kinetic energy of 1 mole of water at 0 oC, the average kinetic energy
of 1 mole of water at 298 K is
(A) the same, and the number of molecules is the same
(B) the same, but the number of molecules is greater
(C) greater, and the number of molecules is greater
(D) greater, but the number of molecules is the same
3.) If the pressure on a given mass of gas in a closed system is increased and the temperature
remains constant, the volume of the gas will
(A) decrease (B) increase (C) remain the same
4.) Which gas has approximately the same density as C2H6 at STP?
(A) NO (B) NH3 (C) H2S (D) SO2
5.) At a temperature of 273 K, a 400. milliliter gas sample has a pressure of 760. millimeters of
mercury. If the pressure is changed to 380. millimeters of mercury, at which temperature will
this gas sample have a volume of 551 milliliters?
(A) 100 K (B) 188 K (C) 273 K (D) 546 K
Get the answers to these questions
Back to the Unit 10 Old Tests Pag
First to help me with these 4 gets brainless HURRYTTT UPPPPP
Answer: It's A
Explanation:
Answer:
A
Explanation:
Chemistry, Good amount of points for help!!
Answer:
Where are all my chemistry geniuses at?
1. The pattern of electronegativities would increase as you go across a period and would decrease as you go down a group in the periodic table.
2. There is a correlation between electronegativity and atomic radius. As electronegativity increases, atomic radius decreases. As electronegativity decreases, atomic radius increases. This would make sense because as a atomic radius increases, them more farther away the electrons are away from the nucleus because of their many subshells making it less electronegative. As atomic radius decreases, the electrons are more closer to the nucleus because of their few subshells making the element more electronegative.
3. There is a correlation between ionization energy and electronegativity. As electronegativity increases, ionization energy increases as well. If it decreases, ionization energy decreases too. This makes sense because the more electronegativity the element, the more they are closer to the nucleus(making them harder to remove) and the more desperate for an electron the atom is.
Explanation:
Hope it helped!
Much of the thermal energy within the Earth comes from atoms that decay. What is another major source of thermal energy within the
Earth?
A. gravitational energy left over from the formation of the Earth
B. thermal energy from the decay of dead plants and animals
c. thermal energy trapped by clouds and water vapor in the atmosphere
D. thermal energy absorbed by the Sun at the Earth's crust
Geothermal energy is heat produced by the Earth itself. It is a resource that may be gathered for human use and is renewable.
The correct option is (D) Thermal energy absorbed by the Sun at the Earth's crust
The friction and gravitational attraction that were produced when Earth was formed more than 4 billion years ago provide a modest amount of the core's heat. The continual production of heat on Earth, however, is mostly caused by the decay of radioactive isotopes like potassium-40 and thorium-232. From the surface to the core, the temperature of Earth increases with depth. The geothermal gradient is the term used to describe this progressive temperature variation. Rock that has partially melted is known as magma, which is gas- and bubble-filled. The lower crust and mantle both contain magma, which occasionally bubbles to the surface as lava.Nearby rocks and subsurface aquifers are heated by magma. Geysers, hot springs, steam vents, undersea hydrothermal vents, and mud pots are among ways that hot water can be emitted.They are all powered by geothermal energy. Their heat may be captured and used directly for heating, or their steam can be used to generate electricity.Learn more about the Geothermal energy with the help of the given link:
https://brainly.com/question/1061324
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A solid turning to a liquid is called..?
Answer:
A physical change.
Explanation:
Have a wonderful day!
An atom of chlorine with a mass number of 37 contains __ protons and __ neutrons.
Answer:
Its in the Explanation
Explanation:
Here's what I got.
Aluminium-27 is an isotope of aluminium characterized by the fact that is has a mass number equal to
27
.
Now, an atom's mass number tells you the total number of protons and of neutrons that atom has in its nucleus. Since you're dealing with an isotope of aluminum, it follows that this atom must have the exact same number of protons in its nucleus.
The number of protons an atom has in its nucleus is given by the atomic number. A quick looks in the periodic table will show that aluminum has an atomic number equal to
13
.
This means that any atom that is an isotope of aluminum will have
13
protons in its nucleus.
Since you're dealing with a neutral atom, the number of electrons that surround the nucleus must be equal to the number of protons found in the nucleus.
Therefore, the aluminium-27 isotope will have
13
electrons surrounding its nucleus.
Finally, use the known mass number to determine how many neutrons you have
mass number
=
no. of protons
+
no. of neutrons
no. of neutrons = 27 − 13 = 14
Your welcome :)
What state of matter has no visible shape and fills its container?
A: solid
B: liquid
C: has
Answer:
B
Explanation:
The children in the class are more than 10 years old
Answer:
The children have spent 5 of there years playing and having the time of there lives and the other 5 years are spent losing and gaining brain sells!
hope this helps:)
so sorry if this is wrong!
How can you ensure the chemical reaction produces the right amount of heat in a hot pack without hurting you?
Answer:
Heat packs that contain iron and water packets: Exposing the solution to air results in the oxidation of the iron (creates rust). The oxidation of the iron is an exothermic process. Heat packs that contain supersaturated sodium acetate: These are reusable, the packs are boiled to dissolve sodium acetate.
Explanation:Thanks for asking question
Which statement(s) below are correct regarding Rutherford's gold foil experiment? Choose ALL that apply.
a. The atom is mostly empty space
b. The mass and positive charge is concentrated in the center of the atom
c. Atoms contain a nucleus
d. Most alpha particles bounced off of the gold foil
Answer:
A,B,C
Explanation:
A state of matter in which the electrons temporarily separate from the protons. Group of answer choices gas plasma liquid Bose-Einstein Condensate
Answer:
Plasma.
Explanation:
In science, matter can be defined as anything that has mass and occupies space. Any physical object that is found on earth is typically composed of matter. Matter are known to be made up of atoms and as a result has the property of existing in states. The three (3) classical states of matter are;
I. Solid.
II. Liquid.
III. Gas
Plasma can be defined as a state of matter in which the electrons temporarily separate from the protons and as a result, it is generally referred to as the fourth (4th) state of matter due to its superheated nature.
what is the frequency if the wave has a wavelength of 670 nm
The frequency : f = 4.478 x 10¹⁴ /s
Further explanationGiven
wavelength = 670 nm = 670 x 10⁻⁹ m = 6.7 x 10 ⁻⁷ m
Required
The frequency
Solution
Wavelength : from the crest to the crest of the next wave or the trough to the trough
Frequency (f): number of waves in one second
Can be formulated :
v = λ x f
f = v / λ
So the frequency is inversely proportional to the wavelength
v = 3 x 10⁸ m/s(speed of light)
Input the value :
f = 3 x 10⁸ m/s : 6.7 x 10 ⁻⁷ m
f = 4.478 x 10¹⁴ /s
what is a displacement reactions
A displacement reaction is the one wherein the atom or a set of atoms is displaced by another atom in a molecule. For instance, when iron is added to a copper sulphate solution, it displaces the copper metal.
A + BC → AC + B
The above equation exists when A is more reactive than B.
A and B have to be either:
Halogens where C indicates a cation.
Different metals wherein C indicates an anion.
[tex]\textsf{what is a displacement reactions? }[/tex]
Answer:[tex]\large \underbrace{ \underline{ \sf Displacement \: reaction}}[/tex]
The reaction in which more reactive element replace a less reactive element from its compound is called displacement reaction.
Ex:-
[tex]\bold{\large Zn+HCl \longrightarrow ZnCl_2+H_2}[/tex]
I. define ionic bonding and describe how it can be formed between sodium and chlorine
ii. state 3 properties of the compound
III. what type of bonds is formed between two atoms of oxygen? describe how it formed
iv. state 3 properties of the substance in question (3) above
PLSSSS