Answer: The surface of early earth was mostly molten and volcanic. The atmosphere was hot and highly toxic.
Explanation: Photosynthetic organisms were present when earth was primarily anoxic. photosynthetic organisms were present when earth was primarily anoxic. the early forms of photosynthesis did not produce oxygen as a waste product. cyanobacteria carry out anoxic photosynthesis. the early forms of photosynthesis did produce oxygen, but it was not enough to make a difference in the atmosphere. the early forms of photosynthesis were carried out in the water, and there was no way for the oxygen to move into the atmosphere.
1
Early earth have been toxic for modern day animals as at that time atmosphere is oxygen free, and cyanobacteris is able to survive due to symbiosis.
What are cyanobacterias?
Cyanobacteria is a group of microorganisms that are related to bacteria but can perform photosynthesis. They are prokaryotic and are thought to be the earliest form of life on the planet.
Early earth atmosphere may proof toxic for modern day animals because at the earliest time, atmosphere is oxygen free means no oxygen is present in the atmosphere. And in the today scenario we can't imagine life without oxygen.
Cyanobacteria were able to suvive in that early atmosphere through alternative option like symbiosis in which a cell merges with another cell in order to the survival of both cells.
Hence life is toxic at the early time because of the absence of oxygen.
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Why do we buy milk by the gallon and a bottle of coke by the liter?
Answer:
In 70s we were not much familiar with coca cola. Pepsi were sold in liter and milk is traditionally sold locally sold in gallon.
Explanation:
Sarah Brew said that unlike to the global brand like coca cola, Pepsi are sold at global level but milk is sold at local level follow the local custom measurement. If we look back in history, the milkman sold milk door to door in the form of quartz and the gallons. Same things consumers expected from seller.
These are two ways that play a role in grocery shopping. That's why the congress make a product list in form of liter and metric and traditional inches , gallons, pounds, milk etc.
Atoms of Group 6 of the Periodic Table are most likely to form ions with
is marble a compound or element?
Answer:
compound
Explanation:
"Marble is typically more than 95% calcium carbonate, perhaps even 99% calcium carbonate, and calcium carbonate is a compound. Marble has a good claim to be recognized as a compound."
Answer: Element
Explanation: No, marble is not a compound, because for a rock to be called marble other characteristics, beyond the chemical composition, have to have specific values. But marble is made up of only one compound, calcium carbonate. Colored marbles do contain small amounts of other chemicals.
How many moles are in 2.3 grams of phosphorus? :(
Answer:
there are 0.074 moles in 2.3 grams of phosphorus
How many significant figures are in 31400
Answer: The Answer Is 3!
In a controlled experiment, a scientist is studying how long it takes parachutes of different sizes to fall to the ground. What is the experimental variable?
if a bar of motilium cost .0.2 dollars how much will 200 bars cost
Answer: 40
Explanation: 0.2 x 200
which of the following questions can be answered by science?
Answer:Is Fruit ripening dependent on the type of light exposed to?
Explanation: Because you can test this theory
c. What is the volume of a rock that has a mass of 75.4 grams and
a density of 3.45g/cm??
Answer:
75.4 gram /3.45 gram/cubic centimeter = 21.855072463768 cubic centimeter
Explanation:
V = m /ρ
where V = Volume, p = Density and m = Mass
Who Ever answers get 30 points (please no guessing)
Signals from _______ and the body's _______ are received by the brain and the spinal cord.
Answer:
Organs and senses.
Explanation:
The central nervous system includes the brain and spinal cord.
Your internal organs and your senses send signals to your brain and spinal cord.
At what temperature would one mole of molecular nitrogen (N_2) have 7.0 × 10^3 J of translational kinetic energy (total internal energy)? Note: the atomic mass of N is 14 g/mol.
Answer:
T = 561.3K
Explanation:
The translational kinetic energy of a gas such as nitrogen is obtained using the formula:
K = 3/2 * n * R * T
Where n are moles of gases (1mole of N₂), R is gas constant (8.314J/molK)and T is absolute temperature (in K)
If the translational energy of the gas is 7.0x10³J:
7.0x10³J = 3/2 * 1 mole * 8.314J/molK * T
T = 561.3KWhich statement would BEST describe the diagram ?
What is limitation of using marbles as models for atoms
Explanation:
I think it really depends on what you are using them for but I would say in general that using marbles means you can't investigate the subatomic particles (electron orbitals, nucleus etc.) and also you can't exactly model atomic binding with marbles as they don't really stick together.
I would say those are the two main things but once again really depends on what they're being used for.
Hope this helped!
please help me out with this
Tony tuns on a fan on when his room becomes uncomfortably hot. The fan is an example of?
A-Electrical Energy changed into heat energy
B-Mechanical energy being changed into electrical energy
C-Electrical energy changed into mechanical energy
D-Heat energy being changed into electrical energy
Please answer im in a rush
Answer:
C-Electrical energy changed into mechanical energy
Explanation:
Energy, according to the law of conservation of energy, is said to neither be created or lost but only interchangeable from one form to another. Energy exists in different forms. The process by which one form of energy changes to another is called TRANSFORMATION of energy.
However, certain household appliances or devices bring about this transformation of energy. For example, in a case where Tony turns a fan on when his room becomes uncomfortably hot. The fan uses an electric source to get powered on, which then facilitates the blades of the fan to move fast in order to bring about a cool atmosphere.
The fan converts ELECTRICAL energy (electric source) into MECHANICAL energy (moving energy).
If the amount of gas and temperature are constant and you double the volume of the gas,
Explanation:
pressure decrease and collision decreases
Scientific Notation - PLEASE HELP!
Q: A wind-up toy that is wound up but not moving...
(drag the check on one)
does not have energy.
has potential energy.
has kinetic energy.
a has both kinetic and potential energy.
Answer:
The correct option is;
Has potential energy
Explanation:
The total mechanical energy of a mechanical toy is given as follows;
Total Mechanical Energy = Kinetic Energy + Potential Energy
During the winding up of the coil, the total energy becomes the kinetic energy
The total energy at the point of winding up of the coil = The kinetic energy supplied to the toy by winding the coil
From the first law of thermodynamics, energy cannot be created nor destroyed but can be changed from one form to another
Due to the coil being prevented from unwinding, the kinetic energy becomes transformed (stored as) into Potential energy of the toy
When the toy is operated it then unwinds the coil bringing about motion and converting back the potential energy to kinetic energy by itself as if it was alive.
Which statement is not correct?
A: Energy is released when a liquid changes into a solid.
B: Particles move faster in the gaseous state than in the liquid state.
C: The carbon atoms in gaseous methane are further apart than those in solid diamond.
D: There is a large decrease in the volume of a solid metal when pressure is applied to it.
Answer:
D
Explanation:
If we put pressure on a solid or a liquid, there is essentially no change in volume.
Matter are anything that is made up of atoms. The quantity of matter can be observed only on the basis of mass and volume calculation. Therefore, the incorrect statement is option D that is there is a large decrease in the volume of a solid metal when pressure is applied to it.
What is matter?Matter is a substance that has some mass and can occupy some volume. The matter is mainly used in science. Matter can be solid, liquid or gas.
Matter is anything that is made up of atoms. Anything around us that can be physically seen and touched are matter. Ice, water and water vapors are example of matter. When we apply pressure on solid, then there is no change in volume of the solid matter.
Therefore, the incorrect statement is option D that is there is a large decrease in the volume of a solid metal when pressure is applied to it.
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If 6.02*10^23 molecules of ammonia react with 12.04*10^23 molecules of hydrogen chloride, how many molecules are in the reaction vessel when the reaction is complete
Answer:
18.06 × 10²³ molecules
Explanation:
Add the two amounts of molecules together.
6.02 × 10²³ + 12.04 × 10²³ = 18.06 × 10²³
You will have 18.06 × 10²³ molecules in the vessel when the reaction is complete. This is because of the Law of Conservation of Mass. Mass is neither created nor destroyed in chemical reactions. You will have the exact number of molecules in the reaction vessel as you did in the beginning. The types of molecules may change, but the number will stay the same.
Convert 23 kg to ounces (2.2 lbs = 1 kg) (1 lb = 16 ounces)
Answer:
23 kgs = 809.6 ounces
Explanation:
given:
1 kg = 2.2 ibs
therefore, 23 kgs = 2.2*23 Ibs = 50.6 Ibs
since, 1 Ib = 16 ounces
therefore, 23 kgs = 50.6*16 ounces = 809.6 ounces
Cell theory states: A. All living things need glucose to survive B. All living things Must have a nucleus surrounding DNA C. All living things are composed of cells D. The basic unit of life is a cell Group of answer choices C & D A & D B, C & D B only
Answer:
C & D
Explanation:
The cell theory states that every living organism are made of some of the smallest functional unit called the cells. The three scientist who contributed to its development are Rudolf Virchow, Theodor Schwann and Matthias Schleiden.
Cell theory says that cell is considered to be the basic unit of our lives and living things are composed of one or more than one cells. The new cells in an organism arises from the existing cells.
One method of rating complexity in scientific disciplines is with respect to the number of variables that are involved in experiments. Using this method, which of the following disciplines is the most complex?
a. Mathematics,
b. Anatomy,
c. Chemistry,
d. Sociology
Answer:
a. Mathematics
Explanation:
There are various scientific studies and their complexity is different from each other. The one study might be difficult for one student but the other student who has interest in the particular subject might find it easy and interesting. Mathematics is the study which involves lot of variables which increase its level of complexity. The scientist may stuck in solution for years due the complexity of the multiple variables.
please help me i will mark brainliest
Answer:
7) Example: Gravitational force
Gravitational force, also known as gravity, is a type of non- contact force.
10) Unbalanced forces can cause an object to accelerate, make a stationary object move, or cause a moving object to stop.
12) Gravitational force, Frictional force, Magnetic force
13) Friction is beneficial when we are walking as it prevents us from slipping.
For the table, find the net force first and that would help us to find the direction and the type of force (balanced/ unbalanced).
As written in Q11, add all the forces together to determine the net force acting on an object. More specifically, add the forces that act in one direction together. Then subtract the forces acting in the other direction.
Let's look at the teddy bear (Q14 -16):
Take note that we have to look at the direction of the arrow not which side the arrow is on (left/ right of the bear).
Total force acting towards the left
= 16 +7
= 23N
Total force acting on the right= 22N
Net force
= 23 -22
= 1N towards the left
Thus, 14) Unbalanced (since the net force is not 0N)
15) 1N
15) 1N16) left
Vase question:
Total downward force
= 11 +33
= 44N
Total upward force
= 25 +19
= 44N
Net force= 0N
17) Balanced
17) Balanced18) 0N
17) Balanced18) 0N19) No direction
Bicycle question:
Total force acting towards the right
= 65 +115
= 180N
Total force to the left= 170N
Net force
= 180 -170
= 10N to the right
20) Unbalanced
20) Unbalanced21) 10N
20) Unbalanced21) 10N22) To the right
Menthol the substance we can smell in mentholated cough drops is composed of carbon, hydrogen and oxygen. A 0.1005 grams sample of menthol is combusted, producing 0.2829 grams of carbon dioxide and 0.1159 grams of water. What is the empirical formula for menthol? If the compound has a molar mass of 156 g/mol, what is its molecular formula?
Answer:
Empirical and molecular formula are both C₁₀H₂₀O
Explanation:
The formula of menthol is CₐHₓOₙ. In the problem we need to find a, x and n.
The combustion of menthol occurs as follows:
CₐHₓOₙ + O₂ → aCO₂ + 1/2 H₂O
That means moles of carbon dioxide are equal to moles of carbon in menthol and moles of hydrogen are twice moles of water.
Moles CO₂ and mass C:
0.2829g CO₂ * (1mol / 44g) = 6.4295x10⁻³ moles CO₂ = Moles C * 12.01 = 0.0772g C
0.1159g H₂O * (1mol / 18g) = 6.4389x10⁻³ moles H₂O * 2 = 0.01288 moles H * 1.0g/mol = 0.01288g H
That means mass of O in the sample is:
Mass O = 0.1005g - 0.0772g C - 0.01288g H = 0.01042g O * (1mol / 16g) = 6.51x10⁻⁴ moles O
Empirical formula is the simplest whole number ratio of moles of each element present in a compound. Dividing each number of moles in moles O (The smaller number of moles):
H = 0.01288 moles H / 6.51x10⁻⁴ moles O = 19.8 ≈ 20
C = 6.4295x10⁻³ moles C / 6.51x10⁻⁴ moles O = 9.9 ≈ 10
O = 6.64x10⁻⁴ moles O / 6.51x10⁻⁴ moles O = 1
That means empirical formula is:
C₁₀H₂₀OAs molar mass of this empirical formula is:
10*12g/mol + 20*1g/mol + 1*16g/mol = 156g/mol = Molar mass of the compound,
Molecular formula is also C₁₀H₂₀O
Carbon-12 and carbon-13 are isotopes of carbon. Which of the following statements is correct?
They both have seven protons in the nucleus.
They both have the same mass number
They both have seven neutrons in the nucleus.
They both have the same atomic number.
Carbon-12 and carbon-13 are isotopes of carbon as both have same atomic number. The correct option is D.
What is an isotope?Isotopes are members of an element family that possess the identical number of protons but differ in their numbers of neutrons.
The atomic number of an element on the Periodic Table is determined by the number of protons in its nucleus. Carbon, for illustration, has six protons and therefore the atomic number is 6.
The three share the position in the periodic table assigned to atomic number 1 and are thus referred to as hydrogen isotopes. The mass of an isotope influences many important properties.
Isotopes can form naturally through radioactive decay of a nucleus or artificially by inundating a stable nucleus with charged particles in a nuclear reactor using accelerators or neutrons.
Thus, the correct option is D.
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List at least three scientific disciplines related to chemistry mentioned or alluded to in the article. The Ozone Hole
Answer: biology, climate Science, astronomy etc.
Explanation:
The scientific disciplines that are related to chemistry mentioned or alluded to in the article are:
• Biology: Biology is a natural science which studies living organisms, and this include their molecular interactions, evolution, physical structure, and chemical processes.
• Astronomy: Astronomy is the study of space, and the universe. In astronomy, the stars, planets, and galaxies are all studied.
• Climate science: Climate science is also referred to as climatology and it's the scientific study of climate.
Answer:
1. Atmospheric science, environmental science, climate science, biology, astronomy, human physiology and medicine
Explanation:
Because I said so
my car is 10.4 feet long. how many inches is that
Answer:
124.8 inches
Explanation:
Which statement describes an intensive property of matter? It is the same for every sample o single substance. O It depends on how a substance was formed. It is the same for every sample of every substance. O It depends on the amount of substance present.
Answer:
B: It depends on how a substance was formed.
Explanation:
took the test
Intensive property is the same for every sample of a single substance.
INTENSIVE AND EXTENSIVE PROPERTIES:
Intensive properties are properties of a substance that does not depend on the amount of matter of that substance but rather on the type of matter. Intensive properties include; melting point, boiling point, temperature, density etc. On the other hand, extensive properties depend on the amount of matter contained in that substance. For example; volume, mass, weight etc. Since intensive properties are not dependent on amount but dependent on type, they must be the same for every sample of a single substance.Hence, intensive property is the same for every sample of a single substance.
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Christina weighs 119 lbs. What is her mass in grams?
Answer:
53977.5g
Explanation:
1lb = 2.205
119 ×[tex]\frac{1lbs}{2.205kg} = 53.9775[/tex]×[tex]\frac{1000g}{1kg}[/tex] = 53977.5g