What must be satisfied for a hypothesis to be useful?
A. It must be theoretical.
B. It must be observable.
C. It must be based on scientific law.
D. It must be testable.
convert 2.39 x 1022 molecules of water into moles of water
Answer:
[tex]0.0397\ \text{mol}[/tex]
Explanation:
Number of molecules of water = [tex]2.39\times 10^{22}[/tex]
[tex]N_A[/tex] = Avogadro's number = [tex]6.022\times 10^{23}\ \text{mol}^{-1}[/tex]
Number of moles is given by
[tex]\dfrac{2.39\times 10^{22}}{6.022\times 10^{23}}[/tex]
[tex]=0.0397\ \text{mol}[/tex]
The number of moles of water is [tex]0.0397\ \text{mol}[/tex].
4. How many Carbon atoms are present in 1.00 mole of methane, CH,?
6.02 x 1025
o
3.01 x 1023
0
6.02 x 1023
o
O
12.04 x 1023
0
Answer: 6.02*10^23
Explanation:
1 mole of anything is 6.02*10^23
1 atom C per CH4
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Answer:
Barb tested the streak and luster.
Explanation:
Pls mark brainliest
Answer:
Mineral size and luster.
Explanation:
How many grams of aluminum in required to produce 17.5 g of hydrogen
Mass of Aluminum = 157.5 g
Further explanationGiven
17.5 g of Hydrogen
Required
Mass of Aluminum
Solution
Reaction
2Al + 3H₂SO₄ → Al₂(SO₄)₃ + 3H₂
mol Hydrogen :
= mass : molar mass
= 17.5 g : 2 g/mol
= 8.75
From the equation, mol Al :
= 2/3 x mol H₂
= 2/3 x 8.75
= 5.83
Mass Al :
= 5.83 x 27 g/mol
= 157.5 g
Students want to replace the material that connects the battery and the bulb in the circuit. Which material would be the best choice?
A Copper, because it is a conductor
B String, because it is flexible.
C Plastic, because it is an insulator.
D Glass, because light energy can move through it.
Answer:
a is ok
Explanation:
if they had gold it would be better but no
What can break light apart
Which compound is formed from its elements by an
exothermic reaction at 298 K and 101.3 kPa?
Answer:
H2O(g) (negative)
Explanation:
What is the chemical formula of CuH10N2O11.
A chemical formula tells us the number of atoms of each element in a compound. It contains the symbols of the atoms of the elements present in the compound as well as how many there are for each element in the form of subscripts.
Hope I helped :)
Pls help me I beg you
Answer:
Es la c
Explanation:
Espero que te ayude
Answer:
D. Nathan applies enough force through pushes to move the piano
Explanation:
What moves the piano is a net force that is applied through the effort of Nathan on the instrument.
Force is a pull or push on a body.
When force is applied on a body, it causes the state of motion of the body to change.
Therefore, if a body has a net force greater than zero, the body will in likewise begin to move. As Nathan pushes on the piano, it will eventually move.
Balance the equation N2 +H20= NH3 + NO
Answer:
N₂ + 3H₂O → 2NH₃ + 3NO
Explanation:
The reaction expression is given as:
N₂ + H₂O → NH₃ + NO
We are to balance this reaction expression.
To do this, assign a,b,c and d as the coefficients that will balance the expression:
aN₂ + bH₂O → cNH₃ + dNO
Conserving N: 2a = c
H: 2b = 3c
O: b = d
let a = 1, c = 2, b = 3 and d = 3
So;
N₂ + 3H₂O → 2NH₃ + 3NO
c) how many atoms of O are in 45.0g of C12H22011
Answer:
6.022×1023 oxygen atoms
Stars A and B have the same absolute brightness and are the same temperature, but when you look in the sky, Star A
looks dimmer. Why is this?
Star Ais closer than Star
B
Star A is farther away than Stars
с
Stars A and B are the same distance
None of the above
Answer:
star a is farther away
Explanation:
Diagram electron configuration of hydrogen (1), sodium (11), K (19) what do they have in common?
They can only hold 2 electrons in the first outershell
how do people and water affect each other?
Answer:
is this for science or another class?
Answer:
Water is peace. They include sedimentation, pollution, climate change, deforestation, landscape changes, and urban growth. ... Each type of change to a landscape will have its own specific impact, usually directly on natural ecosystems and directly or indirectly on water resources.
Explanation:
20 POINTS! SAVE ME PLS!
Which ion below is fluorine most like to form? A) F+1 B) F+2 C) F-1 D) F-2
How many liters are in 3.45 moles of oxygen gas at STP?
A) 2.08 x 10 24 L
B) 110.4 L
C) 77.28 L
D) .15 L
Answer:
22.4L of one mole of any gas
or you can use PV=nRT
3.45*22.4=77.28
Explanation:
What is the mass of reactants in the following equation? N2 + 3H2 ----> 2NH3 Question 3 options: 34.05 amu 31.03 amu 30.02 amu 15.01 amu
Answer:
34.06amu
Explanation:
The reaction expression is given as:
N₂ + 3H₂ → 2NH₃
We are to find the mass of reactants in the equation given;
Here:
Mass of reactants = 2(atomic mass of N) + 3[ 2 x atomic mass of H]
Atomic mass of N = 14.0067amu
Atomic mass of H = 1.008amu
Mass of reactants = 2(14.0067) + 3(2 x 1.008) = 34.06amu
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Answer:
The answer is number 2.
Explanation:
Perform the following conversions. Show your work and give answer in scientific
notation with correct units.
4.390 m → dm
4.39 x 10^1 dm
we need to change the m to dm first then make it in scientifiv notation
What are zebra mussels?
Answer:
The zebra mussel is a small freshwater mussel.
Which organelle packages materials and distributes them throughout the cell?
lysosome
chloroplast
Golgi body
cell membrane
Pleaseee!!
Answer:
golgi body
Explanation:
trust meeeeeeeeeHow many grams in 65 moles of NaCl?
Answer:0.899076923
Explanation:
Na = 22.99
Cl =35.45
Add them together u get the molar mass of NaCl =58.44
Divide 58.44 by 65
U get 0.899076923
starting with the idea of isostasy and ending with plate tectonics, explain how scientists understanding of the earth's crust has changed
Plate Tectonics is the study of the movement and changes in the rocks that make up the earth's crust. Isostasy is the equilibrium in the earth's crust maintained by a flow of rock material in the asthenosphere.
The concept behind pre-continental drift was that in addition to the pressure of contraction, isostatic adjustments also caused the crust's heavier portions to sink and its lighter portions to rise. It was believed that the Earth's interior was a viscous fluid that could support this rising and sinking.Wegener put up the theory that continents can move in 1915 based on fossil data, how coasts appeared to fit together, and other traits, but it was not well received at the time.He noticed that rock ages, and mountain belts match up across the boundaries of continents if you put the continents back together as the "jigsaw puzzle fit" proposes.On continents that are currently divided by water, fossils of identical terrestrial flora and animals have been discovered.New data from the ocean floor, including topography and rock magnetism, played a major role in the development of plate tectonic theory in the 1960s.On the basis of symmetrical patterns, seafloor spreading was hypothesized as a mechanism to propel the migration of the continents.Hence this led to scientists understanding of the earth's crust has changed.
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Water in the atmosphers is in its gas form and is called water vapor. Where does most of the water vapor in the atmosphere
evaporate from?
Answer:
Water vapor can be produced from the evaporation or boiling of liquid water or from the sublimation of ice. Water vapor is transparent, like most constituents of the atmosphere. Under typical atmospheric conditions, water vapor is continuously generated by evaporation and removed by condensation.
Scientists currently use radioactive isotopes in various field. Some radioactive isotopes are used to _____.
•power iasers
•develop new antibiotics
•clone organisms
•date ancient bones
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ur answer is:-
date ancient bones
Scientists currently use radioactive isotopes in various field. Some radioactive isotopes are used to date ancient bones.
What are isotopes?Isotopes are defined as substances having same number of protons but different number of neutrons.Number of protons is characteristic for determining position of elements in the periodic table.
Since,all isotopes have the same number of protons and hence have same position.They have similar chemical properties as they have same number of electrons.
They find applications in the field of nuclear medicine and oil and gas research . There are 2 types of isotopes : stable and unstable
Unstable isotopes are radioactive and are called as radioisotopes.Some of these isotopes are man -made and hence also called as artificial isotopes.Every element has an isotope which is either man-made or natural .
Many properties of isotopes depend on mass which is measured in atomic mass unit. The difference in actual mass and mass number is called mass defect.
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The speed of light in a vacuum is 2.998 x 108 m/s. How long does it take for light to circumnavigate the Earth, which has a circumference of around 24,900 miles? Do not enter "seconds" as part of your answer. Watch your Sig Figs!
Answer:
0.13 s
Explanation:
We'll begin by converting 24900 mile to metres (m). This can be obtained as follow:
1 mile = 1609.344 m
Therefore,
24900 mile = 24900 mile × 1609.344 m / 1 mile
24900 mile = 4.01×10⁷ m
Finally, we shall determine the time taken for light to circumnavigate the Earth, this can be obtained as follow:
Distance = 4.01×10⁷ m
Speed = 2.998×10⁸ m/s
Time =?
Speed = distance / time
2.998×10⁸ = 4.01×10⁷ / time
Cross multiply
2.998×10⁸ × time = 4.01×10⁷
Divide both side by 2.998×10⁸
Time = 4.01×10⁷ / 2.998×10⁸
Time = 0.13 s
Thus, it will take 0.13 s for light to circumnavigate the Earth.
How much heat is necessary to change 10.0 g of water from 20 degrees celsius to 75 degrees celcius?
Answer: 29.6
Explanation:
The amount of heat is necessary to change 10.0 g of water from 20 degrees celsius to 75 degrees Celcius 50 J ( joules).
what is heat?Heat is the transfer of hot energy in the form of potential energy from one source of an object to another source of an object through a medium for the object and the unit of heat is joules.
The amount of heat can be calculated by a formula,
C = Q / ΔT × m
m = mass, Q = total heat, ΔT is changing in temperature.
substituting the value in the equation,
C = 75/ (75-20) 10
C = 50 J ( joules)
Therefore, 50 J ( joules) is the amount of heat necessary to change 10.0 g of water from 20 degrees Celsius to 75 degrees Celcius.
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How many moles are in 4.85 x 10^25 atoms of carbon?
Answer:
4.85 x 10^25
Explanation:
thats what i was told by a calculator
What is the density of a rock that has a mass of 35 grams and a volume of 7.0 g/mL
Answer: 5
Explanation: Density equals mass divided by volume (D=M/V). Thus, 35/7=5.
The density of a rock : ρ = 5 g/cm³
Further explanationGiven
mass = 35 g
volume = 7 cm³
Required
The density
Solution
Density is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
Density formula:
[tex]\large {\boxed {\bold {\rho ~ = ~ \frac {m} {V}}}}[/tex]
ρ = density
m = mass
v = volume
Input the value :
ρ = 35 g : 7 cm³
ρ = 5 g/cm³