Lava is rock that has undergone a physical change and has liquefied. What is known about this change?
The lava gained mass.
The lava was burned into smoke.
The lava can cool back into rock.
The lava lost mass.
Answer:
It is C-The lava can cool back into rock.
Explanation:
The lava can cool back into rock when it under go physical change and has liquefied.
What is lava?Lava is defined as a molten and partially molten rock (magma) that has expelled from the interior of the terrestrial planet earth or a moon into its surface.
Lava is made up of crystal, volcanic glasses and bubbles.
In liquid lava state, the particle are able move around and slide past one another.
When heat energy is removed from the liquid lava, the particle become more strongly attached to one another and the substance transit back into solid rock state.
Thus, the lava can cool back into rock when it under go physical change and has liquefied.
To learn more about lava, refer to the link below:
https://brainly.com/question/20178020
#SPJ6
Which two tools could be used to measure the volume of this eraser?
A. Triple-beam balance
B. Graduated cylinder
C. Tape measure
D. Digital thermometer
Answer:
Graduated cylinder
Explanation:
A graduated cylinder is essentially meant for volume measurement. It is a cylinder that is graduated from zero to a certain number.
The graduated cylinder is gradually filled with water, the volume of water in the cylinder can be known by reading off the graduation on the cylinder, hence the answer above.
Which is the electron configuration for lithium? A. 1s2 B. 2s3 C. 1s22s1 D. 1s12s2
Answer:
C
Explanation:
just took the test on edge
The electron configuration for lithium [tex]1s^{2} 2s^{1}[/tex]. So, the correct answer is C.
Electronic configuration:-The electron configuration of an element describes how electrons are distributed in its atomic orbitals. Electron configurations of atoms follow a standard notation in which all electron-containing atomic subshells (with the number of electrons they hold written in superscript) are placed in a sequence.
Electronic configuration for lithium:-The atomic number of lithium is 3. So, the electronic configuration is as follows:-
[tex]Li= 1s^{2} 2s^{1}\\=(He) 2s^{1}[/tex]
So, the correct option is C.
Learn more about the electronic configuration here:-
https://brainly.com/question/20391416
What is true of neutrons? (3 points)
They have no charge and are located inside the nucleus.
They have no charge and are located outside the nucleus.
They are negatively charged and are located inside the nucleus.
They are negatively charged and are located outside the nucleus.
Answer:
They have no charge and are located inside the nucleus
Carbonyl fluoride, COF2COF2, is an important intermediate used in the production of fluorine-containing compounds. For instance, it is used to make the refrigerant carbon tetrafluoride, CF4CF4 via the reaction 2COF2(g)⇌CO2(g)+CF4(g), Kc=5.002COF2(g)⇌CO2(g)+CF4(g), Kc=5.00 If only COF2COF2 is present initially at a concentration of 2.00 MM, what concentration of COF2COF2 remains at equilibrium? Express your answe
Answer:
.36 M
Explanation:
2COF₂(g)⇌CO₂(g)+CF₄(g)
2 0 0
2 - 2a a a
a x a / (2 - 2a)² = 5
a² / 4 ( 1 -a )² = 5
a / ( 1 - a ) = √20
a / ( 1 - a ) = 4.47
a = 4.47 - 4.47 a
5.47 a = 4.47
a = .82
Concentration of COF₂ in equilibrium
= 2 - 2 a
= 2 - 2 x .82
= .36 M
A chemist decomposes several samples of water into hydrogen and oxygen and weighs or more correctly measures the mass of the hydrogen and the oxygen obtained. The results are as follows sample 1 has 1.5grams of hydrogen and 12grams of oxygen sample 2 has 2grams of hydrogen and 16 grams of oxygen sample 3 has 2.5grams and 20 grams of oxygen
a. Can you summarize these observations in a short statement? Next, the chemist decomposes several samples of carbon dioxide into carbon and oxygen. The results are as follows: sample 1 has 0.5grams of carbon and 1.3grams of oxygen sample 2 has 1.0grams of carbon and 2.7grams of oxygen sample 3 has 1.5grams of carbon and 4.0grams of oxygen
b. Summarize these observations in a short statement?
c. Formulate a law from the observations in (a) and (b)?
d. Formulate a theory that might explain your law in (c)?
Answer:
A. Hydrogen and oxygen combines in a constant mole ratio in all the three water samples
B. Carbon and oxygen are combined in a constant mole ratio in all the three samples of carbon dioxide
C. All pure samples of a compound contain the same elements combined in the same proportion by mass
D. Since the same elements are always combining to form a certain compound, and the atoms of each element has its own mass, the atoms of each element combining to form the compound do so in a fixed proportion by mass.
Explanation:
A. molar mass of hydrogen = 1.0 g/mol; molar mass of oxygen = 16 g/mol
The molar ratio of elements in a compound gives the proportion each element is combined with the other by mass.
molar ratio of hydrogen to oxygen in the samples:
Sample 1: Hydrogen; 1.5/1 = 1.5: Oxygen; 12/16 = 0.75
molar ratio = 1.5/0.75 = 2 : 0.75./0.75 = 1
molar ratio = 2:1
Sample 2: Hydrogen; 2/1 = 2: Oxygen; 16/16 = 1
molar ratio = 2/1 = 2 : 1/1 = 1
molar ratio = 2:1
Sample 3: Hydrogen; 2.5/1 = 2.5: Oxygen; 20/16 = 1.25
molar ratio = 2.5/1.25 = 2 : 1.25/1.25 = 1
molar ratio = 2:1
Hydrogen and oxygen combines in a constant mole ratio in all the three water samples
B. molar mass of carbon = 12 g/mol; molar mass of oxygen = 16 g/mol
molar ratio of carbon to oxygen in the samples:
Sample 1: Carbon; 0.5/12 = 0.04 : Oxygen; 1.3/16 = 0.08
molar ratio = 0.04/0.04 = 1 : 0.08/0.04 = 2
molar ratio = 1:2
Sample 2: Carbon; 1.0/12 = 0.083 : Oxygen; 2.7/16 = 0.168
molar ratio = 0.083/0.083 = 1 : 0.168/0.083 = 2
molar ratio = 1:2
Sample 3: Carbon; 1.5/12 = 0.125 : Oxygen; 4.0/16 = 0.250
molar ratio = 0.125/0.125 = 1: 0.250/0.125 = 2
molar ratio = 1:2
Carbon and oxygen are combined in a constant mole ratio in all the three samples of carbon dioxide
C. All pure samples of a compound contain the same elements combined in the same proportion by mass
D. Since the same elements are always combining to form a certain compound, and the atoms of each element has its own mass, the atoms of each element combining to form the compound do so in a fixed proportion by mass.
How many grams of calcium phosphate is present in a 5.75x10^-4 mol sample of calcium phosphate
Answer:
about1200 bc it isnt ordinary to round the 1200 to the 12th power so your answer will be 12450
Explanation:
Determine whether each statement describes a solution of a strong electrolyte, weak electrolyte, or non-electrolyte.
Has a medium level of conductivity Choose...
Contains a complete solute Choose...
Has little or no conductivity Choose...
Has the highest conductivity Choose...
Contains a completely dissociated solute Choose...
Contains a partially dissociated solute
Answer:
Please find the terms with their correct description in the explanation section.
Explanation:
An electrolyte is a substance that dissociates or ionizes into cations (positive charged ions) and anions (negative charged ions) in an aqueous solution. An electrolyte can either be strong or weak depending on how well it ionizes and its level of conductivity. However, a non-electrolyte neither ionizes in a solution nor conducts electricity.
Based on this;
1. Weak electrolyte: Has a medium level of conductivity i.e. partially conducts electricity
2. Strong electrolyte: Contains a complete solute
3. Non-electrolyte: Has little or no conductivity i.e. cannot conduct electricity because it doesn't dissociate into ions.
4. Strong electrolyte: Has the highest conductivity i.e. conducts electricity very well.
5. Strong electrolyte: Contains a completely dissociated solute i.e. the solute of the electrolyte separates into anions and cations completely.
6. Weak electrolyte: Contains a partially dissociated solute i.e. the ions of the solute do not ionize completely in the solution.
Weak electrolyte, strong electrolyte, non-electrolyte, strong electrolyte strong electrolyte and weak electrolyte are the answers of the each statement.
Has a medium level of conductivity means it conducts partially electricity not fully so we can say that it is a weak electrolyte. It also contains a partially dissociated solute i.e. the solute do not ionize completely into ions in the solution.
Contains a complete solute as well as has the highest conductivity means conducts electricity better refers to Strong electrolyte. It contains a completely dissociated solute i.e. the solute of the electrolyte separates into anions and cations completely so that's why it conducts electricity very well. Non-electrolyte has little or no conductivity means it cannot conduct electricity due to no dissociation into ions.
Learn more: https://brainly.com/question/18000104
How many atoms of lead are in 3.5 moles of lead?
Answer:
2.1 × 10²⁴ atoms Pb
Explanation:
Avogadro's number: 6.022 × 10²³
Step 1: Find conversions
1 mol Pb = 6.022 × 10²³ atoms Pb
Step 2: Use Dimensional Analysis
[tex]3.5 \hspace{3} mol \hspace{3} Pb(\frac{6.022(10)^{23} \hspace{3} atoms \hspace{3} Pb}{1 \hspace{3} mol \hspace{3} Pb} )[/tex] = 2.107 × 10²⁴ atoms Pb
Step 3: Simplify
We have 2 sig figs.
2.107 × 10²⁴ atoms Pb ≈ 2.1 × 10²⁴ atoms Pb
The statements in the table summarize what Johannes Kepler stated in the early 1600s about the motion of planets.
Kepler's Statements
The orbit of a planet around the sun is an ellipse.
As a planet orbits the sun, a line between the planet and the sun sweeps out equal areas during equal periods of time.
There is a mathematical relationship between the time it takes a planet to orbit the sun and the average distance the
planet is from the sun.
Over the last four hundred years, predictions based on his statements have proven true. Which best describes
Kepler's statements?
O hypothesis
O theory
law
explanation
Answer:
it's law
Explanation:
i got it wrong because i put the wrong answer but it was law or c
i hope this help's
Answer: ITS C
Explanation: Its C Laws
is the longest stage of the cell cycle.
Answer:
Interphase is the longest part of the cell cycle, this is when the cell grows and copies its DNA before moving into mitosis.
Explanation:
Answer:
Interphase
Explanation:
BALANCING EQUATION
XCiz(aq) + AgNO3(aq)
X(NO3)2(aq) + AgCl(s)
Answer:
Explanation:
XCL2 + 2AgNO3 aq ----------- 2 AgCl ( aq ) + X (NO3)2
The density of copper is 8.94 g/cm3. An irregular shaped sample of metal is 14 g and displaces a volume of 2.98 mL. (a) Find the density of this unknown metal. (b) Is this metal copper?
Explanation:
(a).The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question
mass of metal = 14 g
volume = 2.98 mL = 2.98 cm³
It's density is
[tex]density = \frac{14}{2.98} \\ = 4.69798657...[/tex]
We have the answer as
4.70 g/cm³
(b).The metal is not copper since it's density is less than that of copper.
Hope this helps you
Oxidation number of the sulfur and chloride in the sulfur tetrachloride?
+1
Its chemical formula is S2Cl2. It contains sulfur in its +1 oxidation state.
6. A quiet sound exerts a pressure of 4.00 x 10^-8 kPa (kPa= kilopascals, a pressure unit). What is this pressure measured in atmospheres if 1 atmosphere =101.3 kPa?
Answer:
GOOGLE MY HUMAN
Explanation:
GOOGLE!!!!!
1. In Parts I and II of the lab, what happened to the electrons of each element to produce the different colors of light? Explain your answers using important terms from the lesson and information provided in the laboratory. (sorry if it's hard to answer it's a lab)
Answer: Electrons must be heated to emitted light. When heat was added to the elements,the electrons absorbs the energy and moves to its excited state. Once the electronstarts to fall back to a lower orbit, it emits energy in the form of light. Thedifferent lights being emitted, depends on their wavelength
Explanation: I did the Quantization of Energy Lab
The density of rubbing alcohol is 0.785g/mL at 25℃.
Calculate the mass of 15.0 mL of the rubbing alcohol.
Calculate the volume of 15.0 g of the rubbing alcohol.
Answer: The temperature is there to confuse you on purpose. Density changes with temp, but in these type of problems, they mean nothing
Explanation:
The formula for density is mass per unit of volume.
[tex]D=m/v[/tex]
We dont have to do any conversions here so it boils down to division and multiplication.
[tex]0.785g/mL=mass/15mL\\0.785g/mL*15mL = mass\\=11.78 grams[/tex]
Now for the second part:
[tex]0.785g/mL=15g/volume\\15g/0.785g/mL = volume\\=19.11mL[/tex]
the liquid immiscible with water is
Which of these statements best explains why chemistry is flexible?
Answer:
It adds new evidence
Explanation:
I just took them exam
A polysaccharide is best described as
A. glucose
B. 1 simple sugar
C. 3 or more simple sugars combined
(!!!MAKE UP A FAKE ANSWER OR ONE THAT MAKES NO SENSE
I WILL REPORT YOU AND DELETE YOUR ANSWER!!!)
Answer:
3 or more simple sugars combined
Explanation:
A polysaccharid molecules consist of a number of sugar molecules bonded together.
Answer:
Explanation:
Explain transmethylation reaction of amino acids.
Answer:Transamination, a chemical reaction that transfers an amino group to a ketoacid to form new amino acids. This pathway is responsible for the deamination of most amino acids. This is one of the major degradation pathways which convert essential amino acids to non-essential amino acids (amino acids that can be synthesized de novo by the organism).
Explanation:
Billy is trying to figure out what type of wood to use for building a model boat. He has a block of wood with a volume of 8.0 cubic centimeters (cm) and a mass of 4.0 grams (g). What is the density of the block of wood in g/cmº to the nearest tenth? 0.5 2.0 4.0 32.0
Answer:
ρ = 0.5 g/cm³
Explanation:
Step 1: Given data
Volume of the block of wood (V): 8.0 cm³
Mass of the block of wood (m): 4.0 g
Density of the block of wood (ρ): ?
Step 2: Calculate the density of the block of wood
The density of the block of wood is equal to its mass divided by its volume. The mathematical expression is:
ρ = m/V
ρ = 4.0 g/8.0 cm³
ρ = 0.5 g/cm³
One mole of X contains how many molecules of X
Answer:
The mole is represented by Avogadro's number, which is 6.022×1023 atoms or molecules per mol
Explanation:
H2S(aq) + Ca(OH)2(aq)
Answer:
CaS + 2H2O is the balanced equation
In Section 3.5, we applied the equations for a particle in a box to the TC electrons in butadiene. This simple model is called the free-electron model. Using the same argument, show that the length of hexatriene can be estimated to be 867 pm. Show that the first electronic transition is predicted to occur at 2.8 x 104 cm-1. (Remember that hexatriene has six TC electrons.)
Answer: DeltaE = 2.83 * 10^4 cm^-1
Explanation:
hexatriene has six TC (pi) electrons
3 C = C BONDS : 3 * 135 = 405 pm
2 C - C BONDS : 2 * 154 = 308 pm
also the TWO CARBON ATOMIC RADIUS AT EACH END : 2 * 44 = 154 pm
therefore length of molecule = 405pm + 308pm + 154pm = 867 pm
now
HoMo = E4 and CoMo = E3
DeltaE = E4 - E3 = (4^2h^2 / 8mL^2) - (3^2h^2 / 8mL^2)
DeltaE = 7h^2 / 8mL^2
DeltaE = 7 * (6.62 *10^-35 Js)^2 / ( 8 * 9.1*10^-31 kg * (867*10-12m)^2)
DeltaE = 5.62 * 10^-19 J
( 1J = 5.034 * 10^22 cm^-1)
therefore
DeltaE = 2.83 * 10^4 cm^-1
Where is panauti??????????????
Answer:
nepal
Explanation:
Answer:
Nepal ..Explanation:
Please mark me as brainliest..what is inside an atom
A tree is shaken to get its fruits down.Why?
Answer:
Because orginisms need to eat the fruit to gain energy
Explanation:
How many NH4+ ions are in 550 mg of (NH4)3PO4?
My professor usually goes over our in class assignment in class and then assigns us a weekly assignment to finish for homework with the problems being similar to what she has explained. We didn't go over one like this and I don't know how to approach it.
Answer:
7.53 × 10²¹ NH₄⁺ ions
Explanation:
Step 1: Given data
Mass of (NH₄)₃PO₄: 550 mg
Step 2: Convert 550 mg to grams
We will use the conversion factor 1 g = 1000 mg.
550 mg × (1 g/1000 mg) = 0.550 g
Step 3: Calculate the moles corresponding to 0.550 g of (NH₄)₃PO₄
The molar mass of (NH₄)₃PO₄ is 132.06 g/mol.
0.550 g × (1 mol/132.06 g) = 4.16 × 10⁻³ mol
Step 4: Calculate the moles of NH₄⁺ in 4.16 × 10⁻³ moles of (NH₄)₃PO₄
The molar ratio of (NH₄)₃PO₄ to NH₄⁺ is 1:3. The moles of NH₄⁺ are 3/1 × 4.16 × 10⁻³ mol = 0.0125 mol
Step 5: Calculate the number of ions in 0.0125 moles of NH₄⁺
We will use Avogadro's number: there are 6.02 × 10²³ NH₄⁺ ions in 1 mole of ions of NH₄⁺.
0.0125 mol × (6.02 × 10²³ ions/1 mol) = 7.53 × 10²¹ ions
How are transuranium elements made?
Explanation:
The transuranium elements are produced by the capture of neutrons
Hope it will help you
Answer:
Explanation:
The transuranium elements are made by capturing the neutrons.
eg- neptunium
hope this helps
plz mark as brainliest!!!!!!!
