Look at the diagram below- what evidence is there that it
represents a chemical change?

Answer:

mixture

Explanation:

Answer:

mixture

Explanation:

Answer:

.0000084

Explanation:

Answer:

The average atomic mass of boron is found to be  

10.80

Explanation:

also u answered it urself

Relative and average atomic mass both describe properties of an element related to its different isotopes. Out of these two Relative atomic mas is more accurate. Therefore, the average atomic mass of boron is 10.80amu. The correct option is option B.

Mass defines the quantity of a substance. It is measured in gram or kilogram. Average mass is the mass of atoms of an element that are isotopes. It can be calculated by multiplying mass of a isotope to natural abundance of that isotope.

Average atomic mass = (mass of first isotope× percent abundance of first isotope)+(mass of second isotope× percent abundance of second isotope)

Substituting the given values

Average atomic mass=( 10 amu ×  19.9%)+(11 amu × 80.1%)

Average atomic mass=10.80amu

Therefore, the average atomic mass of boron is 10.80amu. The correct option is option B.

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Answer:

C. solid iodine subliming into a gas

Explanation:

A physical change is a change that is reversible and can be reversed back into the original product. The atoms and molecules undergoes some rearrangement in the physical change. The process of change in the state of matters are placed under physical change. Solid iodine sublimes into purple gas on heating. The gas is then changed back to iodine crystals after being cooled. Hence, this is an example of a physical change.

Answer:Molarity can be used to calculate the volume of solvent or the amount of solute. The relationship between two solutions with the same amount of moles of solute can be represented by the formula c1V1 = c2V2, where c is concentration and V is volume.

Explanation: c1V1 = c2V2

The equation that can be used to solve the volume of a solution using the molarity equation is:

Molarity (M) = moles of solute (mol) / volume of solution (L)

This equation can be rearranged to solve for the volume of solution:

Volume of solution (L) = moles of solute (mol) / Molarity (M)

By knowing the molarity of the solution and the number of moles of solute, you can substitute these values into the equation to calculate the volume of the solution.

It's important to note that this equation assumes the molarity is given in units of moles per liter (mol/L). If the molarity is given in a different unit, it may need to be converted before using the equation.

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Your question is incomplete, but most probably your full question was.



Which of the following equations can be used to solve volume of a solution using molarity equation?

Volume moles ÷ molarity

Volume-moles + molarity

Volume moles + molarity

Volume = moles x molarity

Answer:

Explanation:

no no knows

Answer:

I wish I was a scientist

Answer:

1:2

Explanation:

For every 4 moles of aluminum, there are 2 moles of aluminum oxide, so the mole ratio when converting from aluminum to alunmimum oxide is

2 moles aluminum oxide:4 moles aluminum. This can be simplified to 1:2.

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ouch that hurts

What is Temperature Calibration? Temperature calibration refers to the calibration of any device used in a system that measures temperature. Most importantly, this usually means the temperature sensor, itself, which is typically a platinum resistance thermometer (PRT or PT-100), thermistor, or thermocouple.

Answer:

The main difference between boiling point and melting point is that the melting point is defined as the temperature at which solid and liquid phases are in equilibrium, whereas the boiling point is the temperature at which the vapour pressure of a liquid is equal to the external pressure

Answer:

Graduated cylinders are designed for accurate measurements of liquids with a much smaller error than beakers. They are thinner than a beaker, have many more graduation marks, and are designed to be within 0.5-1% error. ... Therefore, this more precise relative of the beaker is just as critical to almost every laboratory.

Explanation:

hope this helped!

Answer:

reaction of rubidium with water

Explanation:

rubidium metals react very rapidly with water to form a colourless solution of rubidium hydroxide ( RbOH) and hydrogen gas H2

Answer:

25

Explanation:

Answer:

Explanation:

What is the fastest time trial for the first quarter checkpoint?  

2.02

seconds

What is the slowest time trial for the first quarter checkpoint?  

2.15

seconds

What is the range of times measured for this checkpoint?  

0.13

seconds

Answer:

what each cells job is divided

Explanation:

Answer:

Significant Figure Rules  

Non-zero digits are always significant.

All zeros between other significant digits are significant.

The number of significant figures is determined by starting with the leftmost non-zero digit. The leftmost non-zero...

The rightmost digit of a decimal number is the least significant digit or least significant figure. Another way to look...

Explanation:

Answer:

Explanation-

Water is a compound because it is formed from hydrogen and oxygen, which is irreversible, having different properties but air is a combination of different gases in any proportion.

Answer:

The number of half dollars in the stack of the height of the Gateway Arch in St. Louis is 89,313 half dollars

Explanation:

The given height of the Gateway Arch in St. Louis = 630 ft

The thickness of each half dollar = 2.15 mm

By conversion of factors, we have;

1 feet = 304.8 mm

Therefore;

630 ft. = 304.8 × 630 mm = 192,024 mm

The number of half dollars that will stack up to 630 ft or 192,024 mm, is therefore, given as follows;

The number, n, of half dollars in the stack of the height of the Gateway Arch in St. Louis = The height of the Gateway Arch in St. Louis/(The thickness of each half dollar)

n = 630 ft/(2.15 mm/(half dollar)) = 192,024 mm/(2.15 mm/(half dollar)) = 89,313.49 ≈ 89,313 half dollars

The number of half dollars in the stack of the height of the Gateway Arch in St. Louis = 89,313 half dollars.

Answer:

when the forest burns all the trees die and the ground becomes more fertile.

The mass of forest trees is due primarily due to the presence of carbon in them. When the forest burns the mass is not destroyed as burning does not cause changes in matter.

Law of conservation of mass is a law which states that during a chemical reaction mass is neither created nor destroyed.Rather it is the only form of the matter which changes.

In chemistry, the law of conservation of mass can be  stated as during a chemical reaction the mass of products is always equal to the mass of the reactants.

This law is important in chemistry as it helped scientists to understand that during a chemical reaction substances do not disappear rather they are transformed to new substances of equal mass.

Law of conservation of mass was given in the year 1774 by French chemist Antoine Lavoisier and hence is also known as Lavoisier's law.

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Answer:

I wont get cavities it the dependent variable

Explanation:

Answer:

2.7 Significant Figures

Explanation:

The two significant figure value is "2.7".

Users were required to round up the given value, 2.6765, to two significant numbers in this challenge. Since the given number has no zeroes, all the digits are significant. Therefore, if we need and round the given number to 2 major digits, the number should only have two numbers.

Therefore, the round figure value is "2.7".

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Answer:

Physical

Explanation:

Water is the chemical form of 2 hydrogen and 1 oxygen (H2O)

It is still H2O, as nothing made it chance that formula.

Answer:

Water, wheel and paddles or bucket are the parts and mechanical energy is produced.

Explanation:

The parts of water wheel system are water, wheel and paddles or bucket. The main purpose of water wheel system is to generate useful energy by using the flowing or falling of water on the wheel. We use this water wheel system for the conversion of kinetic energy into mechanical energy such as water mill or hydroelectric plant in which the blades movement is responsible for the generation of electricity.

Answer:

Conversion of kinetic energy to potential energy (chemo mechanical energy)

In the state of rest, the rubber is a tangled mass of long chained cross-linked polymer that due to their disorderliness are in a state of increased entropy. By pulling on the polymer, the applied kinetic energy stretches the polymer into straight chains, giving them order and reducing their entropy. The stretched rubber then has energy stored in the form of chemo mechanical energy which is a form of potential energy

Conversion of the stored potential energy in the stretched to kinetic energy

By remaining in a stretched condition, the rubber is in a state of high potential energy, when the force holding the rubber in place is removed, due to the laws of thermodynamics, the polymers in the rubber curls back to their state of "random" tangled mass releasing the stored potential energy in the process and doing work such as moving items placed in the rubber's path of motion such as an object that has weight, w then takes up the kinetic energy 1/2×m×v² which can can result in the flight of the object.

Explanation:

Answer:

Elastic potential energy------> kinetic energy --------> elastic potential energy

Explanation:

Elastic potential energy is the energy stored in a spiral spring. When a rubber band is stretched, this elastic potential energy is capable of doing work. This energy is just stored inside the rubber band and released when work is done by the rubber band.

Once the rubber band is released and it is in motion, the energy of the rubber is kinetic energy.

The system is similar to a simple pendulum.

Answer:

b and C

Explanation:

Answer:

hydrosphere

Explanation:

Answer:

Just say you expect all the help you need.

Explanation:

Say that you expect to get as much help as you can and that you expect to he welcomed and loved

Answer:

The given statement is false.

Explanation:

Answer:Astrobiology, formerly known as exobiology, is an interdisciplinary scientific field concerned with the origins, early evolution, distribution, and future of life in the universe.

Explanation:

Answer: the branch of biology concerned with the study of life on earth and in space.

Explanation: Astrobiology is an interdisciplinary scientific field concerned with the origins, early evolution, distribution, and future of life in the universe. Astrobiology considers the question of whether extraterrestrial life exists, and if it does, how humans can detect it.

Answer:C

Explanation: on Edge

Answer: letter c is the answer

Explanation: