A community includes
A. all of the living organisms in a specific place at a specific time,
B. all plants, animals, minerals, and water in a specific place at a specific time,
C. only the plants in a specific place at a specific time.
D. only the animals in a specific place at a specific time.
Answer:
answer: A. all of the living organisms in a specific place at a specific time
Explanation:
________________ substances have an equal amount of H+ and OH- ions in solution.
Answer:
Water, and other neutral
Explanation:
That means those substances have pH = 7.
When the amount of H+ is more than the amount of OH- in solution, the substance is acidic ( eg.: Lemon juice ). pH < 7
When the amount of H+ is less than the amount of OH- in solution, the substance is basic ( eg.: Baking soda ). pH > 7
when the surface of a mirror curves inward, like the inside of a bowl, it is called a ____.
A) plane mirror
B) convex mirror
C) concave mirror
D) diffuse mirror
Answer:
C
Explanation:
The answer is always C
Answer:C. Concave mirror
Explanation:
When the surface of a mirror curves inward, like the inside of a bowl, it is called c. Concave mirror.
A typical cell phone uses wavelength of 0.36meters. How much energy does this wave have?
Answer:
55×10^-26 J
Explanation:
We can calculate the energy of the wave from
E= hc/λ
Where
h= Planks constant = 6.6×10^-34 Is
c= speed of light = 3×10^8 ms-1
λ= wavelength of the wave = 0.36 metres
Recall that cell phone use radio waves which belong to the electromagnetic spectrum hence it must possess the speed of light.
E= 6.6×10^-34 × 3×10^8/ 0.36
E= 55×10^-26 J
Hence the energy possessed by 0.36 meters wavelength radio waves is 55×10^-26 J
ASAP NEED HELP PLSSS
A gas occupying a volume of 3.75L at a pressure of 0.980 arm is allowed to expand at constant temperature until its pressure reaches 0.641 atm. What is the final volume of the sample?
Answer:
Volume = 5.73L
Explanation:
Data;
V1 = 3.75L
P1 = 0.980atm
P2 = 0.641atm
V2 = ?
This question involves the use of Boyle's law, which states that, the volume of a fixed mass of gas is inversely proportional to its pressure provided that temperature remains constant.
Mathematically,
V = kP, k = PV
P1V1 = P2V2 =P3V3=........=PnVn
P1V1 = P2V2
V2 = (P1 * V1) / P2
V2 = (0.980 × 3.75) / 0.641
V2 = 5.73L
The final volume of the gas is 5.73L
how many Atoms of chlorine Cl are there in 3.45 mol Cl?
Answer:
2.078x10^24
Explanation:
No. of atoms of chlorine = 3.45 x 6.022x 10 ^23 x 1
= 2.078x10^24
( to find no. of atoms of, heres the formula i was taught No. of atoms = no. of moles x Avogadros constant x no. of atoms in the formula of compound)
Relate dark matter to the development of the universe after the Big Bang. In 3-5 sentences, speculate on how the development of the universe would have been different if there had been no dark matter. In your answer, use the term structures.
Please answer this and ill mark you as brainliest
Answer:
Dark matter also called baronic matter is the matter that makes up 27% of the universe.
In 1933 it was determined as that mass that cannot be seen, that is, the non-visible mass of outer space.
Dark matter also plays a central role in the formation of structures and the evolution of galaxies and has measurable effects on the anisotropy of cosmic microwave background radiation. The composition of this matter is unknown today.
The dark matter component has considerably more mass than the "visible" component of the Universe.
Explanation:
There are certain researchers who say that the appearance of dark matter was before the appearance of the big bang.
A relevant fact of this matter is that dark matter exerts gravity, and that gravity affects the movements of objects.
Despite the fact that nothing is known about its origin, astronomers have amply demonstrated that dark matter plays a determining role in the formation of galaxies and galactic clusters, which could not maintain their cohesion without its existence, but many doubt that it is the remainder / remnant or product of a big bang.
How is a lithium atom (Li) different from a lithium ion (Li+)?
Li has fewer electrons than Li+
Li has more electrons than Li+
Li has fewer protons than Li+
Li has more protons than Li+
Answer:
Li has fewer protons than Li+
Is the equation Zn+HCl > ZnCL2+H2 unbalanced or balanced
Answer:
unbalanced
Explanation:
Cl and H have an extra atom
- Hope that helps! Please let me know if you need further explanation.
Which substance should a student apply to the skin if he or she gets splashed with an acid?
What is the answer ?
Answer:
b
Explanation:
Electromagnetic waves are waves that have no medium to travel whereas mechanical waves need a medium for its transmission.
Which situation describes why a rock sinks in water?
A. Air pressure is greater than the buoyant force.
B. The force of gravity is greater than the buoyant force.
c. The buoyant force is greater than the force of gravity.
D. The rock is less dense than water.
Answer:
b
Explanation:
NEED HELPPP PLSSSSSSSSSS
What is the mole fraction of Ba(OH)2 in an aqueous solution that contains 22.8% Ba(OH)2 by mass?
Answer:
0.03
Explanation:
22.8 g Ba(OH)2 (1 mol Ba (OH)2/ 171.34 g) = 0.133 mol Ba (OH)2
77.2 g H2O (1 mol H2O/18 g) = 4.29 mol H2O
X= molar fraction= mol Ba(OH)2/ mol total
X= 0.133/ (0.133+4.29) = 0.03
0.03 is the mole fraction of [tex]Ba(OH)_2[/tex] in an aqueous solution that contains 22.8% [tex]Ba(OH)_2[/tex] by mass.
What is a mole fraction?The ratio of the number of moles of one component of a solution or other mixture to the total number of moles representing all of the components.
Moles of [tex]Ba(OH)_2[/tex]
Moles = [tex]\frac{mass}{molar \;mass}[/tex]
Moles = [tex]\frac{22.8 g Ba(OH)_2}{171.34 g}[/tex]
= 0.133 mol [tex]Ba (OH)_2[/tex]
Moles of [tex]H_2O[/tex]
[tex]Moles = \frac{mass}{molar \;mass}[/tex]
[tex]Moles = \frac{77.2 g H_2O}{18 g}[/tex]
= 4.29 mol [tex]H_2O[/tex]
The mole fraction of [tex]Ba(OH)_2[/tex]
[tex]\frac{mol Ba(OH)_2}{total \;mol}[/tex]
= 0.03
0.03 is the mole fraction of [tex]Ba(OH)_2[/tex] in an aqueous solution that contains 22.8% [tex]Ba(OH)_2[/tex] by mass.
Learn more about the mole fraction here:
https://brainly.com/question/8076655
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How many total atoms from Carbon are present on the reactant side?
20 points
2CH2+202
O2+HC4
5
2
1
3
Answer:
2 carbon atoms/molecules are present on the reactant side.
hope it helps!
What kind of energy transformations occur when you hit a coconut with a hammer
sound energy, kinetic energy,
i cant think of any more but hope this helps
Answer:
Mechanical to kinetic to sound to heat
Explanation:
Remember that all types of energy transformation end in heat
What is El Nino and La Nina explained? Please help fast
Answer:
el nino: the boy
la nina: the girl
Explanation:
Answer:
el nino is dinosour la nino is fishcat
Explanation:
what are the possible values for standard temperature and pressure
Answer:
0 °C and 1 Atm,
Explanation:
Standard Temperature and Pressure. Standard temperature is equal to 0 °C, which is 273.15 K.
Standard Pressure is 1 Atm, 101.3kPa or 760 mmHg or torr
Balance the following equation by adding the correct mole numbers.
P⁴+Cl²->PCl³
Hey there!
P₄ + Cl₂ → PCl₃
First, let's balance Cl.
There are 2 on the left, and 3 on the right.
To balance this, let's put a coefficient of 3 in front of Cl₂ and a coefficient of 2 in front of PCl₃.
P₄ + 3Cl₂ → 2PCl₃
Now we have 6 on the left and 6 on the right.
Next, let's balance P.
There are 4 on the left and 2 on the right.
Let's change the coefficient in front of PCl₃ from 2 to 4.
P₄ + 3Cl₂ → 4PCl₃
There are now 4 P on each side.
However, now Cl is unbalanced, with 6 on the left and 12 on the right.
We can change the coefficient in front of Cl₂ from 3 to 6.
P₄ + 6Cl₂ → 4PCl₃
So now, we have 4 P on each side and 12 C on each side.
This is our final balanced equation.
Hope this helps!
Answer:
1:1
Explanation:
Took test
how many moles of solute are present in 50.0 ml of 0.20 m kno3
Answer: Volume = 50.0 mL in liters : 50.0 / 1000 = 0.05 L
n = M x V
n = 0.20 x 0.05
n = 0.01 moles of solute
Explanation:
The number of moles of solute are present in 50.0 mL of 0.20 M of KNO₃ solution is 0.01 moles.
How do we calculate moles?Moles will be calculated by using the molarity formula because molarity is define as the no. of moles of solute present in per liter of the solution as:
M = n/V, where
M = molarity of KNO₃ = 0.2 M
V = volume of solution = 50mL = 0.05L
Moles will be calculated as:
n = (0.2)(0.05) = 0.01 moles
Hence required moles are 0.01 moles.
To know more about molarity, visit the below link:
https://brainly.com/question/26528084
What is the correct answer? Please
Answer:
c
Explanation:
Fossil fuels, like coal, oil, and natural gas, are huge, carbon-rich deposits that essentially trapped carbon for millions of years (until humans started burning them for energy).
True or False
Answer:
True!
Explanation:
Fossil fuels are carbon based compounds present deep in the earth left millions of years ago.
hope it helps!
Which formula represents an isomer of CH3−CH2−COOH?
CH3−CO−O−CH3
CH3−CO−CO−CH3
CH3−C−OH−CH3
CH3−CH2−CO2−CH3
Answer:
CH3−CO−O−CH3
Explanation:
i just took the test
PLEASE HELP :"( DUE NOW!!
What is the equation for the equilibrium constant for this equation?
CO+3H2⇌CH4+H2O
[H2O][H2]/[CH4][CO]
[CO][H2]3/[CH4][H2O]
[CH4][H2O]/[CO][H2]3
[CH]4[H2O]/[H2]3
Answer:
The correct answer is
[CH4][H2O]/[CO][H2]3
Option 3 is correct
Explanation:
Step 1: Data given
For the equation aA + bB ⇆ cC + dD
The equilibrium constant is [C]^c * [D]^d / [A]^a*[B]^b
Step 2: Calculate the equilibrium constant Kc
CO+3H2⇌CH4+H2O
Kc = [H2O][CH4] / [CO][H2]³
The correct answer is
[CH4][H2O]/[CO][H2]3
Option 3 is correct
Katie throws a 3 kilogram ball fast at a speed of 15 meters what is the momentum of the ball katie threw
Answer:
Hey!
Your answer is 45kg.m/s
Explanation:
Using the formula P=M x V
(p=momentum...M=mass...V=velocity)
We do M x V
15 x 3
Which gives us an answer of 45kg.m/s!
HOPE THIS HELPS!!
Need help with these three pls!!!!!
how does the sun light affect earths climate
Answer:
The Sun powers life on Earth; it helps keep the planet warm enough for us to survive. It also influences Earth’s climate: We know subtle changes in Earth’s orbit around the Sun are responsible for the comings and goings of the past ice ages. But the warming we’ve seen over the last few decades is too rapid to be linked to changes in Earth’s orbit, and too large to be caused by solar activity
Explanation:
How many atoms are there in 2 moles of helium?
Answer:
1 mole Of Helium = Weight of Helium/4Weight of Helium = 1*4 = 4 grams 1 mole of Helium contains 6.023*10²³ ( Avogadro number) atoms. Number of moles of in 4 grams of Hydrogen 4 grams is = given weight / molecular weight of Hydrogen (H₂) = 4/2 =2 Number of atoms/molecules in 2 moles of Hydrogen is (2*6.023*10²³) atoms. = 12.046*10²³ atoms.
(Hope this helps)
The number of atoms in 2 moles of helium is 1.204×10²⁴ atoms
From Avogadro's hypothesis,
1 mole of any substance = 6.02×10²³ atoms
Thus,
1 mole of helium = 6.02×10²³ atoms
With the above information in mind, we can obtain the number of atoms in 2 moles of helium as follow:
1 mole of helium = 6.02×10²³ atoms
Therefore,
2 moles of helium = 2 × 6.02×10²³ atoms
2 moles of helium = 1.204×10²⁴ atoms
Thus, we can conclude that 2 moles of helium contains 1.204×10²⁴ atoms
Learn more: https://brainly.com/question/24848191
How could you determine if a car door is made of a material, such as plastic?
Answer:Most cars have the visible outer panel, and supporting structure, made from steel. Some use aluminium, at least one series-produced model had magnesium doors, and there are also doors where the visible parts are plastic or fiberglass, with some sort of metal inside for strength.
Explanation:
Answer:
Most cars have the visible outer panel, and supporting structure, made from steel. Some use aluminium, at least one series-produced model had magnesium doors, and there are also doors where the visible parts are plastic or fiberglass, with some sort of metal inside for strength.
Which of these Electromagnetic waves has the most kinetic energy and can be
dangerous?
O radio waves
O gamma rays
O ultraviolet waves
O visible light
Answer:
Gamma Rays.
Explanation:
Gamma-ray photons have the highest energy in the EMR spectrum and their waves have the shortest wavelength.
