When dealing with hazardous materials generated in the lab, the two most important guidelines are: (Choose two.)

Answer:

[tex]1.29 * 10^{24}[/tex] particles of gold

Explanation:

To convert the number of moles of any substance, in this case gold, you need Avogadro's number.

Avogadro's number is always [tex]6.022[/tex] × [tex]10^{23}[/tex]

[tex]2.15[/tex] moles Au × [tex]\frac{6.022*10^{23} particles}{1 mole Au}[/tex] = [tex]1.29 * 10^{24}[/tex] particles of gold

The number of representative particles in 2.15 moles of gold is 1.29 × 10 ²⁴.

The term mole is defined as the amount of  substance containing 6.023 × 10²³ particles. 1 mol = 6.023 × 10²³ particles. This number is also called Avogadro's number. The symbol of mole is denoted by M.

A mole is a very important unit of measurement that chemists use. By using moles, chemists have to measure for very small things like atoms, molecules, or other particles.

The quantity amount of substance is a measure of how many elementary entities of a given substance are present in it.

To convert the number of moles of any substance, we required Avogadro's number.

Avogadro's number is always equal to 6.023 × 10 ²³

2.15 moles Au × 6.023 × 10 ²³ particles / 1 mole of Au

= 1.29 × 10 ²⁴ particles of gold

Thus, the number of representative particles in 2.15 moles of gold is 1.29 × 10 ²⁴.

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Answer:

The correct option is

B. PEA = KEC + PEC

Explanation:

The potential energy is the energy possessed due to position

From the image the point with the highest position and therefore the most potential energy and the lowest or zero kinetic energy is point A

Given that we have;

Total mechanical energy = The potential energy +  The kinetic energy

Where there is constant total mechanical energy in the system, then, at the point A where the kinetic energy is zero, the potential energy is equal to the total mechanical of the system, we have;

Total mechanical energy = The potential energy at A = PEA

Total mechanical energy = PEA

At point C where we have the total mechanical energy presented as follows;

Total mechanical energy = Kinetic energy at C + Potential energy at C

Total mechanical energy = KEC + PEC

Therefore;

PEA = KEC + PEC.

Answer:A copper-gold alloy has a crystalline structure

Explanation:

Answer:

D

Explanation:

Answer:

D

Explanation:

:)

Answer:

It is made up of 2 elements. The elements are calcium and chlorine.

Explanation:

I just know

Answer:

A. Freezing point: Increase.

B. Melting point: Decrease

C. Boiling point:  Decrease​

Explanation:

Answer:

A increase

B decrease

C decrease

Explanation:

Answer:

D

Explanation:

A plant powered by natural gas releases carbon dioxide

In an ecosystem, a plant powered by natural gas releases carbon dioxide which is toxic for the environment.

Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.

Energy enters the ecosystem through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.

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I found this. hope it helps!

Answer:

[tex] \boxed{ \bold{ \huge{ \boxed{ \sf{cubic \: meter \: ( \: {m}^{3} )}}}}}[/tex]

Explanation:

The space occupied by a body or a substance is known as volume. The standard unit or SI unit of volume is cubic meter ( m³ ).

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Best regards! :D

Answer: Model

Explanation: Did the quiz

Answer:

The answer is "brittle,  dense, and electrically insulating"

Explanation:

An iodine sampling frame is cheaper to transport as a powder because it is fragile, simple for individual bits to break.

The helium gas becomes less dense than for the air components for developers inbreathe, thus a helium gas was filled balloon floats throughout the air.

The plastic is the chemical compound of the non-metallic compound, in which it makes a popular layering for electrical cables to prevent unnecessary fleeing the flow.

Answer:

The answer is "brittle,  dense, and electrically insulating"

Explanation:

Given :

Volume of water , V = 63 ml .

To Find :

The volume of the water in [tex]dm^3[/tex] .

Solution :

We know , 1 ml of water is equal to [tex]1 \ cm^3[/tex] .

So , 63 ml of water is :

[tex]V=63 \ cm^3[/tex]     .... equation 1 .

Now , 1 cm = 0.1 dm

Putting value of 1 cm in equation 1 .

We get ,

[tex]V=63\times (0.1\ dm)^3\\V=63\times 10^{-3}\ dm^3\\V=6.3\times 10^{-2}\ dm^3[/tex]

Therefore , the volume of 63 ml water in [tex]dm^3[/tex] is [tex]6.3\times 10^{-2}\ dm^3[/tex] .

Hence , this is the required solution .

Answer:

I wont get cavities it the dependent variable

Explanation:

Answer:

CARBON-HYDROGEN BOND

Explanation:

The non-covalent interactions in the options are the hydrogen bond, the Van der Waal's bond, the dipole-dipole interaction. The odd one out of the options is the carbon - hydrogen bond.

The carbon-hydrogen bond is a covalent bond involving carbon and hydrogen atoms in which carbon shares its outer valence electrons with up to four hydrogen atoms either forming a complete shell with single bonds or complete shells with double or triple bonds. The type of bonding is found in hydrocarbons and other organic compounds. For example the alkanes, alkenes, alkynes and aromatic hydrocarbons.

The non- covalent bonds are the bonds that bind macro-molecules and do not involve the sharing of pairs of electrons. They are much more weaker than covalent bonds and are very important in the formation of proteins and nucleic acids. This type of bonding includes the electrostatic interactions, hydrogen bonds, hydrophobic bonds, Van der Waal's interactions. The different types of the non-covalent bonds differ in geometry, strength and specificity.

So therefore, carbon-hydrogen bond is the odd one of the non-covalent interactions listed in the options.

Answer:

Does the nature of intermolecular forces present in different substance affect their boiling points?

Explanation:

In every scientific research there must be a dependent and an independent variable. These variables are easily deduced from the scientific question that is being investigated.

If a student is comparing the boiling points of different substances having different intermolecular forces, then his or her aim is to establish a relationship between the nature of intermolecular forces present (independent variable) and the observed boiling point of the substance (dependent variable).

This is aptly shown by the research question ' Does the nature of intermolecular forces present in different substance affect their boiling points?'

Options:

Is boiling point affected by the strength of particle attraction?

Is boiling point affected by the mass of the sample?

Is boiling point correlated to melting point?

Is boiling point the temperature at which a substance changes its state?

Explanation:

ADD THE OPTIONS PEOPLE OR YOU GET NON RELATED AWNSERS LIKE THE ONE ABOVE

Answer:

the energy required to do work

Answer:

350 J

Explanation:

The law of conservation of energy states that energy can neither be created nor destroyed but can only be converted from one form to another. This means that in a system, energy is not lost.

In this question, an unlit match contains approximately 1,000 J of chemical energy. When lit, thermal and light energy are emitted i.e. it gets converted to light and heat energy. If the thermal energy emitted was measured to be 400J, and the remaining match still contains 250J of chemical energy, then:

The amount of light energy emitted will be:

Total chemical energy (1000J) - {Remaining chemical energy (250J) + emitted thermal energy (400J)}

= 1000 - (400 + 250)

= 1000 - 650

= 350

Hence, the amount of light energy emitted is 350J

Note that, the amount of energy converted (thermal and light) and remaining chemical energy still equates the total chemical energy in the match.

Answer:

Table salt is made up of two elements

Sodium and Chlorine

Explanation:

[tex]Na + Cl_2 - > NaCl[/tex]

How Rock salt is gotten

: As the brine boils in the first effect, water evaporates producing further steam and causing salt crystals to grow. As the brine boils and the water starts to evaporate, a thick salt slurry of brine and salt crystals is formed.

Explanation:

[tex]\huge\underline\bold\blue{ƛƝƧƜЄƦ}[/tex]

Hope it helps

   Drive only when needed. The best way to reduce the fuel consumption is to simply drive your car less. Drive your car only when you really need to. If you only need to travel a few blocks, consider walking or even riding a bicycle. Not only will you save money at the pump, the exercise will certainly do you some good

   Make sure the gas cap is on tight. One reason you may not be getting the mileage you expect is because there isn't as much gas in your tank as you think. 147 million gallons of gas were lost last year due to evaporation. Why did it evaporate? The gas cap was not on tight. So just make sure it is tight, and it will enable you to keep all the gas you pay for

   Avoid idling. When you do need to drive your car, make sure you avoid idling whenever possible. When your car is running, but not moving, your gas mileage is absolute zero. So if your car will remain stationary for more than a minute or so, switch the engine off. However, only do this when it is safe to do so

   Accelerate and break steadily. While driving, always apply steady and consistent pressure to your car's accelerator pedal. A heavy foot will always result in reduced gas mileage and poor fuel consumption

   Drive the speed limit. Always try to drive at or near the speed limit. The optimal traveling speed for every make and model vehicle is different. However, the faster you drive, the worse your gas mileage and fuel consumption will be. Drive as fast as you need to in order to maintain a safe driving speed. But, save highway driving speeds for the highway and not around town

   Coast when possible. Constantly accelerating and braking only wastes fuel and reduces your car's fuel consumption. So, whenever possible, coast and avoid burning excess fuel. This takes a little practice, but can be a great way to increase the fuel economy of your vehicle

   Use cruise control on the highways. Cruise control means that your car will be going at a constant velocity, which means there is no acceleration. No acceleration reduces the amount of work your engine does, and therefore it uses less gas. You should set your cruise control at the speed limit, because 55 miles per hour is the perfect speed for maximum fuel efficiency

   Make your car more aerodynamic. You can do so by removing the roof racks on top of the car, and also by decreasing the weight of the car by taking out unneeded items

   Keep the windows closed. The more aerodynamic your vehicle remains, the better your car's fuel efficiency. Keeping your windows down while driving creates more drag and wind resistance for your automobile. If you are driving at speeds of less than 35 mph, it is usually okay to keep the windows down. However, at higher speeds, you should keep the windows up order to reduce drag and improve fuel consumption

   Minimize air conditioning. There will be times, of course, when summer heat will cause you to use the air conditioning system. However, use the AC in moderation. If you need to choose between keeping your windows rolled down or using the AC at high speeds, use the air conditioning on a low setting

   Replace dirty air filters. Dirty air filters cause your car's engine to work much harder than it has to and always results in poor fuel economy. So, make sure you follow the manufacturer's recommendation for periodically changing out the air filter. A clean air filter allows your engine to perform more efficiently and also helps you save money at the pump

   Maintain proper tire inflation. Check your car owner's manual and always ensure your tires are inflated to the proper air pressure level. Improperly inflated tires can reduce your car's fuel economy by up to five percent in some cases. This is quite simply a complete waste of fuel and money

   Reduce weight in the vehicle. Get rid of any unnecessary items in your car's trunk or other areas of the vehicle. For every 100 pounds of weight in the vehicle, your car's fuel economy decreases by about one or two percent. By making sure your vehicle remains as light as possible, you can improve the fuel consumption of your vehicle and save money on your fuel bill

Sorry it's really long :P but hope this helped

Answer:

The flame test is important in these fields as it helps scientists in determining the metal ions present in elements under study from their emission spectrum.

Explanation:

The Flame test is an important test in Chemistry that is based on the fact that metal ions emit certain characteristic spectrum. The element under investigation is made to pass through a hot, non-luminous flame. The resulting spectrum emitted determines the present metal ions. It is important in;

1. Forensics: Forensic is the application of scientific methods in detecting crime. If for example, a food substance is poisoned, the flame test can help in determining the metal ions present in the food and to know if they are indeed poisonous.

2. Astronomy: Scientists observe the stars and the spectra emitted by them to know which elements have the same colors. This also helps them to know how many light years away the stars are.

3. Environmental and Industry issues: Some industries may be fund guilty of releasing substances such as in oil exploration or bad water to the environment. Flame tests would help to determine which metal ions are present in these substances and their potential for and degree of harm.

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:

Live Together

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:

s

Explanation:

s

Answer:

Both reflect the kinetic energy of moving particles of matter. However, temperature is the average kinetic energy of particles of matter, whereas thermal energy is the total kinetic energy of particles of matter. ... Another factor also affects thermal energy. The other factor is mass

Explanation: