Answer:
Explanation:
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.
Item 3
Which part of the cell contains the genetic instructions and information?
pores
nucleus
cell wall
plasma membrane
Answer: B.
Explanation:
The nucleus is a membrane-enclosed organelle found in most eukaryotic cells. The nucleus is the largest organelle in the cell and contains most of the cell's genetic information (mitochondria also contain DNA, called mitochondrial DNA, but it makes up just a small percentage of the cell's overall DNA content).
Hope this helps!
Answer:
nuke-leus
Explanation:
Giant kelp has gas-filled sacs to help it float so it can do what?
collect more sunlight
send signals to other plants
trap small fish
move with the ocean waves
Answer:
collect more sunlight
Answer:
to collect more sunlight
Explanation:
I
go to CALIFORNIA VIRTUAL ACADEMY ONLINE SCHOOL WITH K12
Round the value 44.981 g to three significant figures.
Answer:
45.0
Explanation:
Using the rules of rounding, we can round 44.981 to 45. We need that third sig fig though, so we add the trailing zero
The value 44.981 g to three significant figures is 45.0 g.
Significant figures, also known as significant digits, are the digits in a number that carries meaning in terms of precision and accuracy. They indicate the certainty or reliability of a measurement or calculated value.
To round the value 44.981 g to three significant figures, follow the rules for significant figures:
Identify the three most significant digits in the number. They are 4, 4, and 9.
Look at the digit immediately after the third significant digit. If it is 5 or greater, round up; if it is less than 5, round down.
In 44.981 g, the digit immediately after the third significant digit (9) is 8. Since 8 is greater than 5, round up.
Therefore, rounding 44.981 g to three significant figures gives us:
45.0 g.
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What is a material that you cannot see through called?
Answer:
metal
Explanation:
What is the formula weight (amu) of the molecule H2O? Use atomic masses of H and O as 1.008 amu and 16.00 amu respectively. Report answer to 4 sig figs.
Answer:
Formula weight of H₂O molecule is 18.02 amu.
Explanation:
Given data:
Formula weight of H₂O = ?
Atomic mass of H = 1.008 amu
Atomic mass of O = 16.00 amu
Solution:
Formula weight:
"It is the sum of all the atomic weight of atoms present in given formula"
Formula weight of H₂O = 2×1.008 amu + 1×16.00 amu
Formula weight of H₂O = 18.02 amu
Thus, formula weight of H₂O molecule is 18.02 amu.
1) The equilibrium constant Kc of the reaction
A + B ⇄ C + D is equal to 9.
If 0.4 mol of A and 0.4 mol of B are reacted, the number of moles of D formed is:
a) 0.30
b) 0.60
c) 0.40
d) 0.36
e) 0.18
Answer:
a) 0.30
Explanation:
Kc = [C] [D] / ([A] [B])
Set up an ICE table:
[tex]\left[\begin{array}{cccc}&Initial&Change&Equilibrium\\A&0.4&-x&0.4-x\\B&0.4&-x&0.4-x\\C&0&+x&x\\D&0&+x&x\end{array}\right][/tex]
Plug in values and solve:
9 = x² / (0.4 − x)²
3 = x / (0.4 − x)
1.2 − 3x = x
1.2 = 4x
x = 0.3
if you know any answer to this pls help out I'll give brainiest plus a lot of points
Answer:
I cant see it clearly
Explanation:
:(
A given volume of gas at a temperature of 100 K has a
pressure of 225 kPa. At a higher temperature, the same
volume of gas has a pressure of 450 kPa. At what
temperature does the gas have this higher pressure?
Answer:
200K
Explanation:
Pressure is directly proportional to temperature.
100=225
x=450
(100*450)/225=x
x=45000/225
x=200
SnO2 + H2_Sn+ H20 plz help me
Answer:
Tin(IV) Oxide + Dihydrogen = Tin + Water
Explanation:
wasn't ez
What is an individual living entity called?
tissue
cell
organism
organ
Answer:
it is organism the third one
What is the density of Radon (Rn) gas at a temperature of 100°C and a pressure of 0.75
atm?
Answer:
Density of Radon is 5.44 g/.
Explanation:
Given data:
Temperature of gas = 100°C (273+100 = 373 K)
Pressure of gas = 0.75 atm
Density of gas = ?
Solution:
First of all we will derive the formula.
We know that,
PV = nRT
and
n = m/M (m = mass, M = molar mass)
PV = (m/M) RT
PVM = (m/M) RT ×M
PVM = mRT
PVM/V = mRT/V
PM = dRT (m/V = d)
Now we will put the values in formula:
Molar mass of Radon is 222 g/mol .
0.75 atm ×222 g/mol = d× 0.0821 atm.L/mol.K ×373 K
166.5 atm.g/mol = d×30.62 atm.L/mol
d = 166.5 atm.g/mol / 30.62 atm.L/mol
d = 5.44 g/L
What is the atomic number of an atom?
Answer:
The atomic number is the number of protons in the nucleus of an atom. The number of protons define the identity of an element (i.e., an element with 6 protons is a carbon atom, no matter how many neutrons may be present).
Explanation:
The atomic number is the number of protons in the nucleus of an atom. The number of protons define the identity of an element (i.e., an element with 6 protons is a carbon atom, no matter how many neutrons may be present).
Explanation:
The atomic number is number on the right side
Why are some elements no longer found on earth
Answer:
They go extinct
Explanation: When something is on earth and it gets used so much and then it's not in earth anymore that means it was used to much it went extinct (Take dinosaurs for example besides there death)
The elements no longer found on earth are extincted.When something is on earth and it gets used so much and then it's not in earth anymore that means it was used to much it went extinct.
What is element?An element is a atom's species that consist of proton in a proper number embeded in their nuclei, as well as pure substance a species consist of pure substance.
Carbon is an element which is a chemical by nature and it is represented by C and the atomic number of carbon is 6.The atomic structure of carbon is designed in such way that it contain 6 electron, 6 protons, and 6 neutrons.
The atomic mass of carbon is 12.011 u and the carbon contain 2, 4 electrons per shell with the electronegativity of 2.55 .The main function of carbon compounds to maintain earth's atmosphere and temperature and to supply energy that works as fuel for our economy.
The atomic structure of carbon is designed in such way that it contain 6 electron, 6 protons, and 6 neutrons.The atomic mass of carbon is 12.011 u and the carbon contain 2, 4 electrons per shell with the electronegativity of 2.55 .
Therefore,The elements no longer found on earth are extincted.When something is on earth and it gets used so much and then it's not in earth anymore that means it was used to much it went extinct.
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pleaseeeeeeeeeeee help me
Answer:
4740460000, or 4.74046*10^9
Explanation:
This is math i thnk
e means *10
[tex]5.63\cdot \:8.42\cdot \:10^{19-11}[/tex]
[tex]5.63\cdot \:8.42\cdot \:10^8[/tex]
[tex]10^8\cdot \:47.4046[/tex]'
<3
Red
ok so this is saying
5.63 x 10^19 * 8.42 x 10^-11 indicates a scientific notation
plug into your graphing calculator and you get 4740460000 but make it imto three sig figs so the answer is: 4.74 x 10^9
A material will float on the surface of a liquid if the material has a density less than that of the liquid . Given that the density of water is 1.0g/mL will a block of material with a volume of 27.3mL and a mass of 380g sink or float in water .
Answer:
the mass will sink.
Explanation:
because the block of material is still more dense.
An astronaut has a mass of 80kg how much mass does he weigh in Mars
Answer:
26.66kg
Explanation:
If a person has a mass of 80kg, then they will weigh 80kg x 9.8m/s^2 or 784 Newtons on the Earth. That same person would weigh 80kg x 9.8m/s^2/3 or 261.33 Newtons on Mars, which the person might think was 26.66 Kg (although he would be incorrect since his mass has not changed).
WHICH IS WHICH?
Directions: In the given illustrations, identify which are elements and compounds. Write
your answer in the space below the illustration.
plssss i need answers plssssssssssssss its due tmrw
Answer:
- First: element.
- Second: Compound.
- Third: element.
- Fourth: Compound.
Explanation:
Hello.
In this case, since elements are composed the same atom and compounds are composed by two different atoms, we can see that:
- First: it is an element as each sphere seems to be the same.
- Second: It is a compound as two different type of spheres are shown, white and black, considering each sphere is a different element.
- Third: it is an element because the spheres are equal, in fact, it is a diatomic element as two atoms are joined per molecule.
- Fourth: It is a compound as well since each molecule has two colored spheres and one white sphere, meaning that it has two different atoms per molecule.
Best regards.!
For a reaction Y → X with a very high equilibrium constant, K, which of the following is true? You can refer to the following two equations in formulating your answer.$$$$Choose one:A. The standard free-energy change is large and positive.B. The amount of product and substrate are equal at equilibrium.C. The forward reaction rate greatly exceeds the reverse reaction rate at equilibrium.D. The amount of product will be higher than the amount of substrate at equilibrium.
Answer:The amount of product will be higher than the amount of substrate at equilibrium
Explanation:
Recall that the equilibrium constant K depends on the amounts of reactants and products present in the system at equilibrium.
Considering the equation; K = [X]/[Y], as the concentration of X increases above that of Y, the equilibrium constant K becomes very high, hence the answer above.
An element has three isotopes: St-284 (34.60%), St-285 (21.20%), and St-288 (44.20%). What is its average atomic mass?
Answer: I believe that it’ll be 284.45
Explanation:
May have to double check but I’m pretty sure that’s correct sorry if it’s not
PLEASE HELP!!
The scientific method is a process that scientists use to investigate something in the natural world. Which of these best describes the difference between a scientist collecting data and analyzing data?
A -When a scientist collects data the hypothesis is compared to the data. When a scientist analyzes data, data are analyzed, scientists predict future experiments.
B - When a scientist collects data, the scientist develops new ideas for experiments. When a scientist analyzes the data, he or she looks at what could be improved in the investigation.
C - When a scientist collects data, the data include the observations made during the experiment. When a scientist analyzes the data, the scientist communicates his observations to other scientists.
D - When a scientist collects data, he or she record the data from an experiment. When a scientist analyzes the data, he or she decides whether or not the data support the hypothesis.
Answer:
I believe D is the best answer choice.
Explanation:
C is also a good answer but I feel like D most accurately describes the scientific method.
Answer:
C
Explanation:
its true and contains more academic words and i got it right
WILL GIVE BRAINLIEST. If the frequency of X-ray radiation is increased, what changes? I. The number of photons. II. The energy of the radiation. III. The amplitude of the wave. IV. The wavelength of the radiation. I and II I and III I and IV II and III II and IV.
Answer:
II and IV.
Explanation:
To know which option is correct, do the following:
Energy (E) and frequency (f) are related by the following equation:
E = hf
Where:
E is the energy.
h is the Planck's constant.
f is the frequency.
From the equation E = hf
Energy is directly proportional to the frequency. This implies that an increase in the frequency will also increase the energy and a decrease in the frequency will also decrease the energy.
Therefore, (II) in the question above is correct.
Velocity (v), wavelength (λ) and frequency (f) are related by the following equation:
v = λf
Divide both side by λ
f = v/λ
Thus, we can see clearly that the frequency is inversely proportional to the wavelength. This means that an increase in frequency will decrease the wavelength and a decrease in frequency will increase the wavelength.
Therefore, (IV) in question above is correct.
Thus, II and IV are the correct answers.
how are heavy elements such as carbon, oxygen,and neon formed during star formation?
Answer:
Neutron star collisions
How many atoms are in 3.2 pg of Ca? The molar mass of Ca is 40.08
g/mol.
Answer:
4.81×10¹⁰ atoms.
Explanation:
We'll begin by converting 3.2 pg to Ca to grams (g). This can be obtained as follow:
1 pg = 1×10¯¹² g
Therefore,
3.2 pg = 3.2 pg × 1×10¯¹² g / 1 pg
3.2 pg = 3.2×10¯¹² g
Therefore, 3.2 pg is equivalent to 3.2×10¯¹² g
Next, we shall determine the number of mole in 3.2×10¯¹² g of Ca. This can be obtained as follow:
Mass of Ca = 3.2×10¯¹² g
Molar mass of Ca = 40.08 g/mol
Mole of ca=.?
Mole = mass /molar mass
Mole of Ca = 3.2×10¯¹² / 40.08
Mole of Ca = 7.98×10¯¹⁴ mole.
Finally, we shall determine the number of atoms present in 7.98×10¯¹⁴ mole of Ca. This can be obtained as illustrated below:
From Avogadro's hypothesis,
1 mole of Ca contains 6.02×10²³ atoms.
Therefore, 7.98×10¯¹⁴ mole of Ca will contain = 7.98×10¯¹⁴ × 6.02×10²³ = 4.81×10¹⁰ atoms.
Therefore, 3.2 pg of Ca contains 4.81×10¹⁰ atoms.
If I have 21,000 mL of gas at a temperature of 870C and a pressure of 101 atm, what will be the pressure of the gas if I raise the temperature to 1040C and decrease the volume to 15 liters?
Answer:
We have,
Initial volume is V
1
Initial temprature is T
1
=75
0
C
Initial pressure is P
1
So, final temprature is T
2
=273+75=348K
V
2
=V
1
−
100
15
V
1
=
100
85V
1
Applying the gas formula,
T
1
P
1
V
1
=
T
2
P
2
V
2
348
P
1
V
1
=
T
2
×100
2P
1
×85V
1
T
2
=
100
2×85×348
T
2
=591.6K
heating a solid candle wax
What is answer
Physical or chemecal
Answer:
it will change its physical property from solid into liquid
CHEMISTRY! 50 POINTS! What is the original pressure of 20.0L of compressed gas if the pressure changes to 560.0mmHg when the volume is decreased to 15700mL?
Answer:
The answer is 439.60 mmHgExplanation:
To find the original pressure we use the formula for Boyle's law which is
[tex]P_1V_1 = P_2V_2[/tex]
where
P1 is the initial pressure
P2 is the final pressure
V1 is the initial volume
V2 is the final volume
Since we are finding the original pressure
[tex]P_1 = \frac{P_2V_2}{V_1} \\[/tex]
From the question
V1 = 20 L = 20,000 mL
P2 = 560.0mmHg
V2 = 15700mL
We have
[tex]P_1 = \frac{560 \times 15700}{20000} = \frac{8792000}{20000} = \frac{2198}{5 } \\ [/tex]
We have the final answer as
439.60 mmHgHope this helps you
What changes a liquid to a gas?
Answer:
evaporation
Explanation:
Answer:
boiling (or vaporization)
Explanation:
At a certain temperature, the particles in a liquid have enough energy to become a gas. This process of a liquid becoming a gas is called boiling (or vaporization.)
Which of the following elements would be most
likely to be both conductive AND magnetic in nature?
A. F
B. Ni
C. Na
D. Xe
Answer:
Ni ➡️Nickel
Explanation:
The element that is most
likely to be both conductive AND magnetic in nature is "Nickel".
Nickel is a popular magnetic metal and it is known to be ferromagnetic. It's valuable in alloys and used in the production of stainless steel. The element belongs to the transition metals - hard, malleable and ductile. It has high electrical and thermal conductivity.
The element finds usefulness in batteries, phones, kitchen tools, jewellery, etc.
4. Which of the following is the most stable isotope?
Polonium-210
Uranium-237
Francium-227
Plutonium-238
Half-life
(hr)
3,310
162
0.04
768,000
A. Polonium-210
B. Uranium-237
C. Francium-227
D. Plutonium-238
Answer: D. Plutonium-238 is the most stable isotope
Explanation:
Radioactivity is the process of unstable isotopes to stable isotopes by decay, by emitting certain particles (such as alpha (α), beta (β), gamma (γ) particles)
General formulas used in decay:
T = duration of decay
t 1/2 = half-life
N₀ = the number of initial radioactive atoms
Nt = the number of radioactive atoms left after decaying during T time
Half-life shows the time it takes for an atom to get half of its initial mass (to decay to half of its initial mass)
The longer the half-life indicates the stability of the atom
Half-life (hr) of isotopes :
Polonium-210 : 3,310
Uranium-237 : 162
Francium-227 : 0.04
Plutonium-238 : 768,000
The half-life value above shows that Plutonium-238 has the longest time, making it the most stable
The longer the half life of an isotope higher will be its stability. Here, among the given isotopes, plutonium - 238 has the greater half life. Hence it is the mist stable one.
What is half life ?Heavy unstable radioactive isotopes undergoes nuclear decay through the emission of charged particles such as alpha or beta. The unstable isotopes then converts to other stable nuclei or to isotopes with more half life.
Half life of a radioactive isotope is the time required to decay the half of initial amount of the isotope. It is inversely proportional to the decay constant of the nuclear decay.
Among the given isotopes, Pu-238 has the longer half life time. Longer half time means more time to get decayed by half then more stability. Thus, Pu-238 is the most stable one.
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Question 2
Calculate the velocity of a pickup truck with a de Broglie wavelength of 1.27 10-38 m and a
mass of 2347 kg
Explanation:
de Broglie wavelength= h/mv
v=h/m x de Broglie wavelength
v= (6.626× 10^-34)/ (2347× 1.27 × 10^-38)
v= 22.229 m/s(according to Google scientific calculator)
am sorry I don't hv a calculator at hand