Which series of words describes lengths of geologic time from shortest to longest?
era
period
eon
era
Answer:
eon,era, period
Explanation:
Answer:
period<era<eon
Explanation:
I took the test, sadly got a 70%.
At 150°C, water is a:
solid
liquid
gas
Answer:
gas
Explanation:
it would evaporate
Write chemical equations from the given word equations: Magnesium + Oxygen à Magnesium Oxide Hydrogen + Oxygen à Water Methane + oxygen à Carbon dioxide + Water
Answer:
1. 2Mg + O2 —> 2MgO
2. 2H2 + O2 —> 2H2O
3. CH4 + 2O2 —> CO2 + 2H2O
Explanation:
1. Magnesium + Oxygen —> Magnesium Oxide
Mg + O2 —> MgO
There are 2 atoms of O on the left side and 1 atom on the right side. It can be balance by putting 2 in front of MgO as shown below:
Mg + O2 —> 2MgO
There are 2 atoms of Mg on the right side and 1 atom on the left side. It can be balance by putting 2 in front of Mg as shown below:
2Mg + O2 —> 2MgO
Now the equation is balanced.
2. Hydrogen + Oxygen —> Water
H2 + O2 —> H2O
There are 2 atoms of O on the left side and 1 atom on the right side. It can be balance by putting 2 in front of H2O as shown below:
H2 + O2 —> 2H2O
There are 2 atoms of H on the left side and a total of 4 atoms on the right side. It can be balance by putting 2 in front of H2 as shown below:
2H2 + O2 —> 2H2O
Now, the equation is balanced.
3. Methane + oxygen à Carbon dioxide + Water
CH4 + O2 —> CO2 + H2O
There are 4 atoms of H on the left side and 2 atoms on the right side. It can be balance by putting 2 in front of H2O as shown below:
CH4 + O2 —> CO2 + 2H2O
There are 2 atoms of O on the left side and a total of 4 atoms on the right side. It can be balance by putting 2 in front of O2 as shown below:
CH4 + 2O2 —> CO2 + 2H2O
Now, the equation is balanced.
Explain what would happen if the Mid-Atlantic Ridge stopped creating new land.
(At least 3 sentences please :D)
Answer:
There will be no new land for the plant and other organisms or resources.
Explanation:
The Mid-Atlantic ridge is one of the seafloor expanding which is a process in which due to the presence of magma or lava a pressure form under the seafloor or seabed that two plates moving away from one another.
The gap between these plates is filled with lava which leads to the formation of new rocks and land after cooling down, which provides soil, nutrients for the various resources, and leads to new biodiversity. If there will be no land formation there will be no new resources or the ecosystem will be there.
A. What are the stable isotopes of carbon?
B. What are the stable isotopes of nitrogen?
ahhh help
Answer:
carbon-12 (12C) and carbon-13 (13C).
nitrogen-14 (14N) and nitrogen-15 (15N)
I need to wright an essay on bacteria so what topic in bacteria is good for me to wright about?
St. Louis, Missouri, is located near the middle of the United States. On June 21, the noon Sun rays hit St. Louis at an angle of 75°. On December 21, the noon Sun rays hit at an angle of 28°. How will this affect the temperature in St. Louis on these dates?
Answer:
The temperature will be colder on December.
Explanation:
It is given that the angle of the sun rays on June 21st on St. Louis, Missouri hits at 75° angle. And on December 21st, the sun rays are at an angle of 28°.
Now, St. Louis, Missouri is located in the middle of United States which is in the Northern hemisphere.
From here, we can conclude that the temperature of St. Louis, Missouri on December 21st will be much colder as the rays of the Sun is at a much lower angle on the surface than on the 21st June. Due to this lower angle of the sun rays, the energy of the sun will be more spread out and will be less concentrated on the surface on 21st December when compared to 21st June. Also the days are much shorter in December than in June.
Which of these would be a chemical change?
A. Seashells are ground to power by the surf.
B. Salt from the soil dissolve into a stream.
C. An icicle forms along cliff edge.
D. Lightning strikes of spruce tree and start a fire.
Answer:
I'm between B, C, and D
Explanation:
Becasue all of them can become in a chemical change but what is thing is that B or C will be the ones because they can turn into something will the lighting strike won't turn the Tree into something the tree will stay the same
A student measures the length of a magnesium ribbon three times and records the data as: (a). 23.486 cm, (b). 23.491 cm, (c). 23.511 cm, The labeled value of the magnesium ribbon is 23.490 cm. Calculate the precent error for ALL the data recorded by the student. Which has the least percentage error? (Show all work or an explanation)
Explanation:
A student measures the length of a magnesium ribbon three times and records the data as: (a). 23.486 cm, (b). 23.491 cm, (c). 23.511 cm
The labeled value of the magnesium ribbon is 23.490 cm
We need to find the precent error for all the data recorded by the student.
[tex]\text{Percentage error} = \dfrac{|\text{calculated value-actual value}|}{\text{acutal value}}\times 100[/tex]
(a) When the calculated value = 23.486 cm
[tex]\text{Percentage error} = \dfrac{23.486 -23.490 }{23.490 }\times 100\\\\=0.017\%[/tex]
(b) When the calculated value = 23.491 cm
[tex]\text{Percentage error} = \dfrac{23.491 -23.490 }{23.490 }\times 100\\\\=0.0042\%[/tex]
(c) When the calculated value = 23.511 cm
[tex]\text{Percentage error} = \dfrac{23.511 -23.490 }{23.490 }\times 100\\\\=0.0893\%[/tex]
When the calculated value is 23.486 cm, it has least error of 0.017%.
The relationship between the Kelvin temperature and volume of a gas is linear until the temperature begins to approach 0 K. why?
Answer:
See explanation
Explanation:
We must remember that gases exhibit ideal gas behavior at ordinary temperature and pressure.
As the system approaches absolute zero gas laws begin to break down and the relationship linear between volume and temperature (Charles law is broken).
Recall that, at absolute zero, the volume of an ideal gas would be zero and all molecular motion stops due to the fall in temperature and kinetic energy of the molecules.
The reason for linear should be explained below.
Temperature:Since the system approaches absolute zero gas laws starts to break down and the relationship is linear between volume and temperature At absolute zero, the volume of an ideal gas should be zero and all molecular motion stops because to the fall in temperature and kinetic energy of the molecules.
Learn more about the temperature here: https://brainly.com/question/19258620
Who is credited with discovering the neutron
Answer:
James Chadwick
Explanation: By 1920, physicists knew that most of the mass of the atom was located in a nucleus at its center, and that this central core contained protons. In May 1932 James Chadwick announced that the core also contained a new uncharged particle, which he called the neutron.
What type of chemical reaction does this equation represent?
2 Al + 3 FeO --> Al2O3 + 3 Fe
single replacement
O synthesis
combustion
O double replacement
Answer:
Single Replacement
Explanation:
Synthesis Reactions:
A + B → AB
Combustion Reactions:
CₓHₐ + O₂ → CO₂ + H₂O
Double Replacement Reactions:
AB + CD → AD + CB
Single Replacement Reactions:
A + BC → AB + C
Given RxN: 2Al + 3FeO → Al₂O₃ + 3Fe
We are replacing one element, therefore it is a single replacement reactionHELP ME PLEASE
i appreciate it in advance :)
Answer:
C
Explanation:
The valence electrons should be the ones reacting
Answer:
Only electrons in the outermost shell can participate in chemical reactions!
Explanation:
Calculate the frequency and the energy of blue light that has a wavelength of 300 nm
Explanation:
Like all EM waves, light transports energy across space. The intensity (energy per unit area and unit time) is proportional to the square of the amplitude of the electric field of the light wave. This energy, however, arrives at a receiver not continuously but in discrete units called photons. The energy transported by an electromagnetic wave is not continuously distributed over the wave front. It is transported in discrete packages. Photons are the particles of light.
Properties of photons:
Photons always move with the speed of light.
Photons are electrically neutral.
Photons have no mass, but they have energy E = hf = hc/λ. Here h = 6.626*10-34 Js is a universal constant called Planck's constant. The energy of each photon is inversely proportional to the wavelength of the associated EM wave. The shorter the wavelength, the more energetic is the photon, the longer the wavelength, the less energetic is the photon.
A laser beam and a microwave beam can carry the same amount of energy. In this case the laser beam contains a smaller number of photons, but each photon in the laser beam has a higher energy than the photons in the microwave beam.
Photons can be created and destroyed. When a source emits EM waves, photons are created. When photons encounter matter, they may be absorbed and transfer their energy to the atoms and molecules. Creation and destruction of photons must conserve energy and momentum. The magnitude of the momentum of a photon is p = hf/c = h/λ.
Problem:
What is the energy of a photon of blue light (λ = 450 nm) and of a photon of red light (λ = 700 nm) in units of eV = 1.6*10-19 J?
Solution:
E = hc/λ.
Blue light: E = (6.626*10-34 Js)(3*108 m/s)/(450*10-9 m) = 4.4*10-19 J = 2.76 eV
Red light: E = (6.626*10-34 Js)(3*108 m/s)/(700*10-9 m) = 2.8*10-19 J = 1.8 eV
Problem:
A 100-W incandescent light bulb uses 100 W (100 W = 100 J/s) of electrical power but only radiates about 15 W of actual visible light. Roughly how many visible photons per second hit the open pages of a typical hardcover book if the pages are about 2 m from the bulb and face it directly?
Solution:
We have to make a variety of estimations and approximations to solve this problem.
To find the number of photons hitting the pages each second, we have to know the light energy hitting the pages per second and the energy per photon. We could compute the latter if we knew the wavelength of the light, but the visible light emitted by a normal incandescent bulb is a mix of wavelengths.
Let us estimate that the average wavelength of the visible light is about 550 nm, which is in the yellow region of the spectrum. This means that the average energy per photon is about
E = hc/λ = (6.626*10-34 Js)(3*108 m/s)/(550*10-9 m) = 3.61*10-19 J = 2.26 eV.
To find the number of photons hitting the pages of a book, we need to know the energy per second that falls on the pages. Let us assume that the light energy from the bulb travels uniformly in all directions. Imagine a sphere centered on the light bulb with a radius R = 2 m. Every second, 15 J or so of visible light energy crosses this sphere. If the light energy is spread uniformly over the sphere, then the intensity of the visible light or the energy per unit area per unit time in units of W/m2 at any point on the inner surface of the sphere will be
I = Plamp/(4πR2),
Electrons are ejected from a metal surface with speeds ranging up to 4.6*105 m/s when light with a wavelength of 625 nm is used.
(a) What is the work function of the surface?
(b) What is the cutoff frequency of the surface?
Select all properties that you included in your hypothesis. . . . High melting and boiling points and therefore solid at room temperature . . . A crystalline structure . . . Ability to dissolve easily in water . . . Ability to conduct electricity well
Answer:
High melting and boiling points and therefore solid at room temperature
A crystalline structure
Ability to dissolve easily in water
Ability to conduct electricity well
Explanation:
The hypothesis mentioned in the question will be something like this
'If a substance is solid at room temperature, has a crystalline structure, dissolves easily in water, and conducts electricity well, then it likely contains ionic bonds. Otherwise, it likely contains covalent bonds'
We can see that all the items selected in the answer box were included in the hypothesis.
Answer:
C, B, D
good luck on your Chem!
comment if you have any questions!
How do diffusion and osmosis differ?
Thank you
Answer:
Osmosis is the movement of solvent particles across a semipermeable membrane from a dilute solution into a concentrated solution. ... Diffusion: Diffusion is the movement of particles from an area of higher concentration to lower concentration. The overall effect is to equalize concentration throughout the medium.
9. When the vapor pressure of a liquid is equal to the
atmospheric pressure, the liquid will
A) freeze
B) boil
C) melt
D) condense
Which of these accurately describes a chemical reaction?
A. Products and reactants combine to form new reactants
B. Products and reactants combine to form new substances
C. Products combine to make reactants
D. Recatants combine to form products
Answer:
D
Explanation:
its just right
Answer:Reactants combine to form Products. Hope this helped! ;)
Explanation:
Which of the following best describes the arrangement of electrons in a metallic bond?
-Electrons are transferred from one atom to another.
-Electrons exist as shared electron pairs between neutral atoms.
-Electrons are delocalized in a "sea of electrons" and are shared among the positively charged metal ions.
-Electrons are shared unequally, creating a bond with partial positive and negative poles.
Help ASAP please
Answer:
-Electrons are delocalized in a "sea of electrons" and are shared among the positively charged metal ions.
Explanation:
In a metallic bond, electrons are delocalized in a sea of electrons and are shared among the positively charged metal ions.
- In a metallic bond, there is delocalization of electrons. The electrons are shared in between the atoms, rather than getting transferred. So, there is no transfer of electrons.
- The electrons are delocalized and shared alongside the nuclei of the atom. There is no existence of electrons around the neutral atoms.
- In the metallic bonds electrons are delocalized and are shared among the positively charged atomic nuclei in the form of a sea of electrons. Thus, electrons are delocalized in a sea of electrons and are shared among positively charged metal ions.
- There is an equal sharing of electrons in the bond. No unequal and partial sharing is there.
For more information about the metallic bond, please refer the link:
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What is the density of water (H20) at 4°C, which is just above the freezing point?
Answer:
1.0 g/cm3
Explanation:
Water behaves anomalously since it contracts when cooled from any temperature until 4°C and begins to expand below this temperature. Thus water expands when cooled between 4°C to 0°C.
It then follows that water has its maximum density at 4°C. The maximum density of water is 1.0 g/cm3. This is the density of water at 4°C.
Would bread mold and toenail fungus be made of eukaryote or prokaryote cells?
Answer:
eukaryotic !
Explanation:
all fungi are eukaryotic .
This organelle allows materials to get into and out of the cell. What am I?
a. Cell Wall
b. Nucleus
c. Cell Membrane
s. Ribosomes
ques-1 Write true and false for the following :-
1)tearing of paper is a physical change
2) The presence of oxygen and water is necessary for rusting of iron
3) Copper is more reactive than iron
4) A physical change can we reserved.
5) In a chemical change ,no new substance is formed
Ques-2 Complete the analogies.
1) Acetic acid:vinegar:: ...........lime water.
2) Copper sulphate : blue vitriol:: ........green vitriol
3) Physical change: ........... :: chemical change:permanent
4) Oxide of iron: .............. : : oxide of magnesium :MgO
5) Saline water: salt water :: soda water:
HELP ASAP PLZ!!An object with a mass of 7.5g raises the level of water in a graduated cylinder from 25.1 mL to 30.1 mL. What is the density of this object?
Answer:
P=1.50 g/mL
this is the answer☺
Hop it helps you!
Which negative quality does Deborah exhibit?
Answer: Disdain
Explanation: Deborah believes that people of other nationalities are inferior to her. she treats them with disdain and does not miss an opportunity to abuse them.
dimension analysis of universal gravitation constant
omg im so dumb i cant answer this question omg sorry im 302918291802832908310 years old and i cant think propertly
Click all the types of energy that is involved after a car fills with gasoline and drives down the road.
Question 1 options:
chemical
solar
mechanical
nuclear
Chemical and mechanical energy is involved after a car is filled with gasoline and driven down the road. So the correct options are A and C.
What are chemical and mechanical energy?
Chemical energy is the energy that is stored in the bonds of any chemical compound. The chemical energy can be released when a chemical reaction is occurring, most commonly in the form of heat. These kinds of reactions are called exothermic reactions.
The reactions that need an input of heat energy to proceed and that may store an amount of that energy as chemical energy in their newly synthesized bonds are called endothermic reactions.
For example, the chemical energy in food is converted into mechanical energy and heat energy in the body.
Mechanical energy is defined as the sum of kinetic energy and potential energy. Kinetic energy is the energy of motion and potential energy is the energy stored in a system because of the position of its parts.
In a system that has only gravitational forces, mechanical energy is constant. This is an otherwise idealized system. This means that this lacks dissipative forces like forces of friction and of air resistance.
Therefore the correct options are A and C.
Read more about chemical and mechanical energy, here
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how do calcium and fluorine become stable when they form calcium fluoride?
Answer:
Explanation:
It occurs as the mineral fluorite (also called fluorspar), which is often deeply coloured owing to impurities. ... Calcium reacts with fluorine to form the compound CaF2. ... (lead is very close) as hydrogen the bond would be considered ionic! ... What is the most stable monatomic ion formed from nitrogen?
Answer:
CaF2 is stable when it is formed because Ca loses two of its electrons. Both accept one electron each. now the Calcium is satisfied because it lost its two electrons and is now behaving like a noble gas, which is what they all want to be like The Flourine is satisfied because they both gained one electron, allowing them to have 8 valence electrons also like a noble gas.
The key is in the 8 valence electrons! Ca has to lose two to have 8, and F has to gain one to have 8fluorinefluorines...
Explanation:
Which of the following is an alkali metal?
Answer: They are lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr)
Explanation: Have a great day-
Answer:
Lithium
Explanation:
Ap3x
THESE ARE CONSIDERED AS THE MALE GAMETES.
Answer:
Nobody cares
Explanation:
Cause nobody cares hope this helps