Explanation:
A physical change is one that alters the physical properties of matter (particularly the form and state).
A chemical change is one in which new kind of matter is formed. It is always accompanied by energy changes (evolution or absorption of energy in form of heat or light or both).
Now, the salient differences between physical and chemical changes;
Physical changes are easily reversible whereas chemical changes are not easily reversible. Physical changes lead to the production of no new kinds of matter whereas chemical changes leads to the production of new kinds of matter. Physical changes involves no change in mass whereas chemical changes involves change in mass. Physical changes require little energy whereas considerable amount of energy is needed for chemical changes.Answer:
The result of a chemical change is a different composition and is often hard to reverse; in a physical change, the composition remains the same and is often easy to reverse.
Explanation:
How many atoms are in a sample of 2.89 moles of potassium (K)?
Answer:
The answer is
1.74 × 10²⁴ potassium atomsExplanation:
To find the number of atoms given the number of moles we use the formula
N = n × Lwhere n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question
n = 2.89 moles
We have
N = 6.02 × 10²³ × 2.89
We have the final answer as
1.74 × 10²⁴ potassium atomsHope this helps you
CCC Energy and Matter Recall that force = mass x acceleration. Explain why the
acceleration of a model rocket increases over time, even if the force from the
burning of the rocket fuel remains constant.
Answer:
The mechanical device inside just gets the energy of the fuel and not the actual liquid.
Explanation:
The acceleration increases since the mechanical device is getting the energy of the fuel and not the fluid.
Just an idea
The information regarding the acceleration of a model rocket should be explained below;
The following information should be considered:
The mechanical device i.e. inside just gets the energy of the fuel but not the actual liquid.The acceleration increases because the mechanical device is getting the energy of the fuel however not the fluid.Learn more: https://brainly.com/question/1979431?referrer=searchResults
Two atoms in the same molecule are linked together by a
chemical ______
Answer: Chemical bond. Two atoms in the same molecule are linked together by a chemical bond. Write "bond" in the blank.
Two atoms in the same molecule are linked together by a chemical bond.
What is chemical bond ?A chemical bond is defined as the formation of a chemical compound by the union of two or multiple atoms, ions, or molecules, the firmness can be evaluated by the type of its chemical bond.
Ionic Bond is a type of chemical bond where relocation of electrons from one atom to alternative atom, one atom creates a negative charge called as anion while another atom creates a positive charge called cation.
The covalent bond defines the distribution of electrons among atoms, it can be either polar or non polar in nature and the electrons are united unevenly in polar covalent chemical bonding.
Hydrogen Bonding is a fragile procedure of chemical bonding, this type of polar covalent bonding occur between oxygen and hydrogen where hydrogen develops a partial positive charge in the formation of the water.
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Please help ASAP I’ll make you u as brainlister please 100 points pelaseee
Answer:
(C) im pretty sure is the answer
Explanation:
Answer:
C
Explanation:
Are hemoglobin formation and functioning brains and muscles benefits of Iron?
Which statement about the layers would they identify as correct?
Ben makes five paper helicopters with different wing lengths. He drops them the same way from a height of two meters for five trials each. He records the amount of time it takes for each helicopter to fall to the ground. What is the independent variable?
Answer:
Wing length
Explanation:
According to the given excerpt, independent variable is 'wing length' and dependent variable is 'amount of time it takes for helicopter to hit the floor'.
Independent variable refers to the variable that do not undergo any change or shift in the course of the experiment of research. The other variables are measured using the constant independent variable. The value obtained from the independent variable is independent. On the other and, the dependent variable witnesses change with respect to the independent variable.
6.82
A 2.10-mole sample of crystalline acetic acid, ini-
tially at 17.0°C, is allowed to melt at 17.0°C and is
then heated to 118.1°C (its normal boiling point) at
1.00 atm. The sample is allowed to vaporize at.
118.1°C and is then rapidly quenched to 17.0°C, so
that it recrystallizes. Calculate AH° for the total pro-
cess as described.
Answer:
0 kj
Explanation:
melting/initial temperature = 17.0°c
boiling point = 118.1°C
pressure = 1.00 atm
2.10 mole sample of crystalline
attached below is the detailed solution required
How many cesium atoms are in 21.9 grams?
Burning 1 kg of coal releases about 3 million joules of energy. If you could use all of the chemical energy to lift another kilogram of coal, how high could you lift it?
I could lift 3.06 x 10⁵ m high
Further explanationEnergy is the ability to do work. Energy can change from one energy to another
Potential energy is the energy that an object has because of its position
The potential energy can be formulated:
Ep = m. g. h
E = potential energy of an object, joule
m = object mass, kg
g = gravity acceleration, m / s²
h = height of an object, m
energy of coal = 3.10⁶ J
mass = 1 kg
g = 9.8 m/s²
[tex]\tt h=\dfrac{E}{m.g}\\\\h=\dfrac{3.10^6}{1\times 9.8}=3.06\times 10^5`m[/tex]
what is the original name for gold
Answer:
It's Anglo Saxon.
Explanation:
From the Latin aurum, which stands for Aurora, the dawn goddess, comes the symbol Au. Early humans were aware of and highly valued gold. Gold is a beautiful and valuable metal that has been used for at least 5500 years. The original name for gold is Anglo-Saxon.
The element number 79 for gold is Au. Gold's Latin name, Aurum, or shining morning, and its earlier Greek origins predate the Anglo-Saxon term for it. It is one of the more abundant elements with a higher atomic number and exhibits very little reactivity towards the majority of atmospheric conditions, such as water and air.
Although gold is typically inert, it can react with a substance called aqua-regia. A substance called aqua regia is used to dissolve gold. Nitric and hydrochloric acids are combined to make them. The oxidizing agent will be nitric acid, which will result in the creation of gold ions.
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Please help me with this I’ve been on this question for 10 minutes now...
Answer:
A
Explanation:
we know that pangea was when all the continents were connected and the tectonic plates moved, causing pangea to split into multiple pieces. so north america was formed by moving tectonic plates.
i hope this helps :))
HELP QUICK What is the mass of an object that has a volume of 2 ml and a density of 10g/ml?
Answer:
The answer is 20 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volumeFrom the question we have
mass = 10 × 2
We have the final answer as
20 gHope this helps you
What is a stable electron configuration?
Calorimetry Gizmo
The answer for Calorimetry Gizmo this lab is hard to find answer but I just save you so yeah :)
Answer:
The answer is JEDDBDDD
Explanation:
A sample of gas has a volume of 10 ml at 2 atm. The pressure increases to 4 atm. What is the new volume?
Answer:
The answer is 5 mLExplanation:
In order to find the new volume 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 new volume
[tex]V_2 = \frac{P_1V_1}{P_2} \\[/tex]
We have
[tex]V_2 = \frac{10 \times 2}{4} = \frac{20}{4} \\ [/tex]
We have the final answer as
5 mLHope this helps you
As part of a chemistry experiment, Sam notes that the temperature at which liquid mercury
freezes into a solid is -102 Fahrenheit (F). The beaker of liquid mercury provided to him Is
at a room temperature of 68". By how many degrees will Sam have to cool the liquid
mercury for it to freeze into a solid?
-102"F
-34°F
102°F
170°F
o
Answer:
-34¨F
Explanation:
1.why does gravity exist?
2.what does the strength of gravity on?
3.what will have stronger force of gravity, jupiter or earth ?
This class is science !!
Answer:
Gravity exists because elementary particles (electrons, quarks, and neutrinos), are NOT static with time and expansion. Matter is dynamic; elementary particles must continually accrete energy (the quanta of space) in order to conserve the continually increasing angular momentum of the expanding universe.
Strength of gravity
9.80665 m/s 2
Jupiter
For lunch you have a glass of sweetened ice tea. The glass contains crushed tea leaves, sugar, a slice of lemon, and both liquid and frozen water (ice cubes). Which of the following categories of matter best describes the contents of the glass? *
Answer:
I think solids
Explanation:
sorry if its not right
A + ion (positive ion, one with extra positive charge)?
Answer:
If an ion has a positive charge then it has lost an electrons.
Explanation:
So you don't "gain" anything when the ion has a positive charge. It loses an electron which means it has more protons than electrons. Thus, the ion has a positive charge. If it "gained" an electron then it would have a negative charge.
3. describe how unequal heating causes weather
Answer:
The uneven heating causes temperature differences, which in turn cause air currents (wind) to develop, which then move heat from where there is more heat (higher temperatures) to where there is less heat (lower temperatures).
Explanation:
When copper is bombarded with high-energy electrons, X rays are emitted. Calculate the energy (in joules) associated with the photons if the wavelength of the X rays is 0.154 nm.
Answer:
E = 12.92 × 10^(-16) J
Explanation:
Formula for energy is;
E = hc/λ
Where;
h is Planck's constant = 6.63 x 10^(-34) J.s
c is speed of light = 3 × 10^(8) m/s
λ is wavelength = 0.154 nm = 0.154 × 10^(-9) m
E = (6.63 x 10^(-34) × 3 × 10^(8))/(0.154 × 10^(-9))
E = 12.92 × 10^(-16) J
The energy associated with the photons of X rays with a wavelength of 0.154 nm is 1.29 × 10⁻¹⁵ J.
When copper is bombarded with high-energy electrons, X rays, with a wavelength of 0.154 nm (λ) are emitted.
We can calculate the energy (E) associated with the photons of these X rays using the Planck-Einstein relation.
[tex]E = \frac{h \times c }{\lambda } = \frac{(6.63 \times 10^{-34}J.s ) \times (3.00 \times 10^{8}m/s ) }{0.154 \times 10^{-9} m } ]= 1.29 \times 10^{-15} J[/tex]
where,
h: Planck's constantc: speed of lightThe energy associated with the photons of X rays with a wavelength of 0.154 nm is 1.29 × 10⁻¹⁵ J.
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What is each quantity of the length of a pencil
Answer:
In units of measurement of length we use centimeter (cm) to measure. We can use this unit for measuring the length of a pencil, the width of a book etc. but this unit is too big to measure the thicken of a pencil. So we use another unit called millimeter (mm).
Explanation:
A single atom of an element has 11 protons, 11 electrons, and 12 neutrons. Which element is it?
OV
Na
Mg
Se
Answer:
Sodium has a mass number of 23amu. Since sodium has 11 protons, the number of neutrons must be 23 – 11 = 12 neutrons.
Explanation:
The mass number is given at the top left of the elements symbol, for example, sodium has a mass number of 23.
Sodium (Na) square from the periodic table. The mass number (23) is top-left. The atomic number (11) is bottom-left.
We know that the atomic number of sodium is 11. This tells us that sodium has 11 protons and because it is neutral it has 11 electrons.
The mass number of an element tells us the number of protons AND neutrons in an atom (the two particles that have a measurable mass).
Sodium has a mass number of 23amu. Since sodium has 11 protons, the number of neutrons must be 23 – 11 = 12 neutrons.
What is a graph?
A graph is a _______________________ representation of the relationship between two quantities.
_______________________ variable (manipulated)
Controlled by experimenter
_______________________________ variable (responding)
Something we observe as the result of the experiment
*Visual
*Independent
*Dependent
What is the oxidation number of Gallium?
Answer: +3
Explanation: Gallium liquefies just above room temperature. Gallium is a soft solid, however it quickly becomes liquid when heated.
If a substance has a density GREATER
than the liquid it's in, then it will
Answer:
sink
Explanation:
a substance with a higher density than others will sink and vice versa
How many atoms of aluminum are in a molecule of magnesium aluminum oxide (Al2MgO4)?
Answer:
12
Explanation:
One of the uses of methanol (CH3OH) in dilute form is as a windshield washer antifreeze. In pure form, methanol has a molar concentration of 24.7M. How many moles are contained in 500 mL of solution?
Mole itself is the number of particles contained in a substance
1 mole = 6.02.10²³ particles
Mole : the ratio of the amount of substance mass and its molar mass
[tex]\large{\boxed{\boxed{\bold{mole=\frac{mass}{molar\:mass}}}}[/tex]
Molarity is a way to express the concentration of the solution
Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution
[tex]\large{\boxed {\bold {M ~ = ~ \frac {n} {V}}}[/tex]
Molar concentration of methanol=24.7 M
Volume of solution = 500 ml = 0.5 L
[tex]\tt mol=M\times V\\\\mol=24.7\times 0.5\\\\mol=12.35[/tex]
Matter is anything that takes up space and can be described by physical and chemical properties. Which statement
BEST differentiates chemical properties from physical properties?
A)
Physical properties are properties that can be physically seen or touched,
while chemical properties can only be found when matter is mixed with
specific chemicals.
B)
Physical properties are measured when matter changes its physical state,
while chemical properties can only be measured if matter remains in one
state for an extended time.
C)
Physical properties are difficult to measure because they require special
tools to detect, and chemical properties are easy to measure and require
not special tools to detect.
D)
Physical properties can be measured/observed without changing matter
into something else, while chemical properties describe matter's ability to
react/combine with other matter.
Answer:
D)
Physical properties can be measured/observed without changing matter
into something else, while chemical properties describe matter's ability to
react/combine with other matter.
Explanation:
Physical Change
The changes that occur only due to change in shape or physical properties but their chemical or internal composition remain unchanged.
1 = These changes were reversible.
2= They have same chemical property.
3= These changes can be observed with naked eye.
Example :
Water converting to Ice
Water converting to gas
In this water molecule remain the same only they rearrange themselves that change its state of mater not composition
Chemical change:
The changes, that occur due to change in the composition of a substance and result in a different compound is known as chemical change.
1 = These changes are irreversible
2 = These changes occur due to chemical reactions
3 = These may not be observed with naked eye
Example:
Combustion of fuel or wood: that oil or wood convert into energy, CO₂ and ash in case of wood
Boiling of egg: that change the chemical composition of protein in the egg .
The reaction of Hydrogen and oxygen:
H₂ (g) + O₂ (g) → 2H₂O (l)