Daffodil is ordering office supplies for her company. When she tries to order pencils, she finds that pencils are sold by the gross, which is equal to 144 pencils. Daffodil checks how many pencils her company uses in a year, and decides to order 5 gross of pencils. How many pencils will she receive? Remember to include units (full word, plural, WATCH YOUR SPELLING) as they are worth half of this question.

6 elements are solid at freezing

Answer:

1 Sodium, 1 Aluminum (1 Sulfur, 4 Oxygen)

Explanation:

hope that helps

Answer:

: the average human-driven CO2 emissions per year climbed 1.4%

every household makes about 7 tons worth of Co2

A C02 footprints are produced at such high rates and hurts plants and the environment

B coal is a very inexpensive and efficient way to generate electricity. Since its a large quantity of them which still produces alot co2  unlike wood, burning wood doesn't  produce as much but it's much harder to ignite and get to last because it takes coal almost 100 degrees and wood takes about 700 degrees

I believe it is False

Answer:

its the sun

Explanation:

Answer:

c = 0.898 J/g.°C

Explanation:

1) Given data:

Mass of water = 23.0 g

Initial temperature = 25.4°C

Final temperature = 42.8° C

Heat absorbed = ?

Solution:

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

Specific heat capacity of water is 4.18 J/g°C

ΔT = 42.8°C - 25.4°C

ΔT = 17.4°C

Q = 23.0 g ×  × 4.18 J/g°C × 17.4°C

Q = 1672.84 j

2) Given data:

Mass of metal = 120.7 g

Initial temperature = 90.5°C

Final temperature = 25.7 ° C

Heat released = 7020 J

Specific heat capacity of metal = ?

Solution:

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

ΔT = 25.7°C - 90.5°C

ΔT = -64.8°C

7020 J = 120.7 g ×  c ×  -64.8°C

7020 J = -7821.36 g.°C ×  c

c = 7020 J / -7821.36 g.°C

c = 0.898 J/g.°C

Negative sign shows heat is released.

Answer:

392g

Explanation:

The given compound is;

         Cr₂(SO₄)₃

To find the molar mass, we sum the atomic masses of the elements in the compounds together.

Atomic mass of Cr  = 52

                           S  = 32

                            O  = 16

So;

 Molar mass  = 2(52) + 3[32 + 4(16)]  = 392g/mol

Answer:

470.4N

Explanation:

Given parameters:

Mass of Stephanie  = 48kg

Unknown:

Force she exerts while falling to the ground  = ?

Solution:

The force she exerts is her weight;

  Weight  = mass x acceleration due to gravity

  Now insert the parameters ands solve ;

  Weight  = 48 x 9.8 = 470.4N

Answer:

723 torr

Explanation:

Using the formula;

P1V1/T1 = P2V2/T2

Where;

P1 = initial pressure (torr)

V1 = initial volume (Litres)

T1 = initial temperature (°C)

P2 = final pressure (torr)

V2 = final volume (L)

T2 = final temperature (°C)

Based on the information provided in this question, V1 = 4.40L, P1 = 555 torr, T1 = 33.0 °C + 273 = 306K, V2 = 3.50 L, P2 = ?, T2 = 44.0 °C + 273 = 317K.

Using the formula above:

555 × 4.4/306 = P2 × 3.5/317

2442/306 = 3.5P2/317

Cross multiply;

2442 × 317 = 306 × 3.5P2

774114 = 1071 P2

P2 = 774114 ÷ 1071

P2 = 722.79

P2 = 723 Torr

Answer:

Clouds form when the invisible water vapor in the air condenses into visible water droplets or ice crystals. For this to happen, the parcel of air must be saturated, i.e. unable to hold all the water it contains in vapor form, so it starts to condense into a liquid or solid form.

Explanation:

MARK ME BRAINLIEST!!!!!!!! THANKS BESTFRIENNNNNDDDDD!!!!!!!!

Answer:

Clouds form when the invisible water vapor in the air condenses into visible water droplets or ice crystals. For this to happen, the parcel of air must be saturated, i.e. unable to hold all the water it contains in vapor form, so it starts to condense into a liquid or solid form.

Explanation:

I HOPE THIS HELPS*--- *meow*

Answer:

Low melting point

Explanation:

Transition metals have the following properties:

Conductivity (Electrical and Thermal)

Malleability (You can hit it with a hammer to mold it)

High melting point

Answer:

Low melting point

Explanation:

Most transition metals property is high melting point.

Answer:

6 months and 1 day

Explanation:

Answer:

4.32 [tex]\frac{1}{18.01}[/tex] ×[tex]\frac{22.4}{1}[/tex] = 5.37

Explanation:

22.4 is how many liters per mole. 18.01 is the mass of H2O.

Answer:

a region around a magnetic material or a moving electric charge within which the force of magnetism acts. hope it helps :)

Answer:

is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials

Explanation:

Answer:

By far the most abundant volcanic gas is water vapor, which is harmless. However, significant amounts of carbon dioxide, sulfur dioxide, hydrogen sulfide and hydrogen halides can also be emitted from volcanoes.

Answer:

yes, some can

Explanation:

because like salt an other compounds by being decomposed

Yes they can be not all the time but sometimes,helps it with weather including heat and freezing temperatures

Answer:

The chemistry of iron is dominated by the +2 and +3 oxidation states i.e. iron(II) and iron(III) complexes e.g. Fe2+ and Fe3+ complex ions with selected ligands, usually of an octahedral shape, a few tetrahedral iron(III) complexes are mentioned too. The reactions of the aqueous ions iron(II) and iron(III) with ammonia, sodium hydroxide and sodium carbonate are described and explained as are complexes of iron(III) with the chloride ion and cyanide ion.

principal oxidation states of iron, redox reactions of iron, ligand substitution displacement reactions of iron, balanced equations of iron chemistry, formula of iron complex ions, shapes colours of iron complexes, formula of compoundsExplanation:

Answer:

I'm pretty sure its liver and pancreas

Explanation:

the pancreas delivers the digestive juice to the small intestine through small tubes, your liver makes the digestive juices called the bile that helps digest fats and some vitamins

Answer:

the answer is liver and pancreas

Answer:

The Rock does not contain carbonate in it.

Explanation:

Limestone(CaCO_3) when reacts with a acid produces carbon dioxide, which comes out as bubbles in the solution. It means the 4th rock does not have carbonate in it. Carbonate minerals are unstable in contact with hydrochloric acid. When acid begins to effervesce (fizz) on a specimen. These bubbles confirms the presence of carbonate in mineral.

Answer:

no,exept y and z are similar

Explanation:

litterly what it says '-'

Answer:

B. Mass in motion. Is the definition of momentum

Answer: The United States

The United States is the only country to have successfully conducted crewed missions to the Moon, with the last departing the lunar surface in December 1972.

Explanation:

Answer

Only the United States has successfully landed men on the moon.

Explanation:

The United States is the only country to have successfully conducted crewed missions to the Moon, with the last departing the lunar surface in December 1972.

Answer:

5. Element J has the highest atomic number

6. Elements G and L have the same number of electrons in their outermost shell.

Explanation:

The periodic table of elements is a table which shows the arrangement of the elements in the order of increasing atomic number. Starting from the topmost left-hand side of the table where the element with the least atomic number is placed, and going across the table from left to right and down to the lowest point to the right of the table, where the element with the highest atomic number is located, the atomic number of elements progressively increases.

Looking at the table, it can be seen that the element J is found at the lowest point to the right of the table. Therefore, element J has the highest atomic atomic number.

6. In the periodic table, elements are arranged into groups and periods. The groups are the columns while the periods are the rows. Elements in the same column or group have the same number of electrons in their outermost shell. Therefore, element G and L have the same number of electrons in their outermost shell.

Sample left = 6.25 g

The percentage = 6.25%

Further explanation

Given

t1/2 = half-life = 3.8 days

t = decay time = 15.2 days

No = initial sample = 100 g

Required

Nt = final sample left

The percentage

Solution

General formulas used in decay:  

[tex]\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{t/t\frac{1}{2} }}}[/tex]

Input the value :

[tex]\tt N_t=100.\dfrac{1}{2}^{15.2/3.8}\\\\N_t=100.\dfrac{1}{2}^4\\\\N_t=6.25~g[/tex]

The percentage : Nt/No

6.25 : 100 = 6.25%

Displacement Reaction:

A displacement reaction is the one wherein the atom or a set of atoms is displaced by another atom in a molecule. For instance, when iron is added to a copper sulphate solution, it displaces the copper metal.

A + BC → AC + B

The above equation exists when A is more reactive than B.

A and B have to be either:

Halogens where C indicates a cation.

Different metals wherein C indicates an anion.

Question:-

[tex]\textsf{what is a displacement reactions?   }[/tex]      

Answer:

[tex]\large \underbrace{ \underline{ \sf Displacement \: reaction}}[/tex]

The reaction in which more reactive element replace a less reactive element from its compound is called displacement reaction.

Ex:-

[tex]\bold{\large Zn+HCl \longrightarrow ZnCl_2+H_2}[/tex]

Answer:

Examples of measured numbers: The diameter of a coin, such as 10.2 mm. The weight of an object, such as 8.887 grams. The length of a pen, such as 12 cm.

Explanation:

Answer:

It completely depends on what you are measuring, what instrument you are using, and the uncertainty associated with your measurement.

Explanation:

When expressing a measurement, there is always going to be a part that you know, and a part that you guess. They both make up known numbers collectively called significant figures (commonly shortened to "sig figs"). For instance, imagine you are measuring the length of a pencil. Let's say it is a typical ruler with divisions of 0.1 cm (picture for reference). You measure the pencil, and to your eyes it looks like it is about 9 cm and 5 small tick marks (so, 0.5 cm), so we'll call that 9.5 cm. Now, this is a known value, so you are certain that it is a least 9.5 cm. However, it may be true that there is one more decimal place that can be known. The general rule is that you want to add one more uncertain digit to the rightmost side of the number, and how many digits depends on the divisions of the instrument. Our ruler has divisions of 0.1 cm (the small tick marks), and so we will go one more place out, and add another digit. Now, let's say our eyes are pretty good, so let's say it's 9.5 cm, and then add that one uncertain digit, a 0 to the smallest division of 0.1, so, 0.10. The final measurement we record is 9.50 cm. Now, it may seem like we are simply guessing or even being unreasonable in our assessment of how long this pencil is. I can promise you that not knowing the actual measurement of this pencil will not make a spaceship crash because of a specification that was not the "right measurement". For those life-or-death measurements, much more precise measurement machines are used; this is just a pencil. Also, it would be unreasonable to say that it is 9.500000 cm or 9.500001 cm. We do not have that kind of certainty with this ruler, only divisions of 0.1 cm, so we can only estimate out to one more decimal place.

In short, find the smallest division of a ruler or whatever device (like a chemical beaker) you are using, and then add one uncertain digit to the end of that. If it's 0.1 cm, then add one digit to that. (example: 5.6 --> 5.63; 3 because that is what it looks like on the ruler). If it's 1 cm, then add an extra .1, so the measurement is 1.1 cm. And of course, it's not always cm you are using, that was just an example. Best of luck!

What was the experiment?

Answer:

D

Explanation:

you should repeat an experiment at least 3 times

Answer:

Alpha

Explanation:

^4 _2 He = alpha

^0 _-1 b = beta

^0 _0 y = gamma

Answer:

The answer is B. Van der Waals forces are weaker than ionic and covalent bonds.

Explanation:

In general, if we arrange these molecular forces from the strongest to weakest, it would be like this:

Covalent bonds > Ionic bonds > Hydrogen bonds > Dipole-Dipole Interactions > Van der Waals forces

Covalent bonds are known to have the strongest and most stable bonds since they go deep and into the inter-molecular state. A diamond is an example of a compound with this characteristic bond.

Ionic bonds are the next strongest molecular bond following covalent bonds. This is due to the protons and electrons causing an electro-static force which results to the strong bonds. An example would be Sodium Chloride (NaCl), which when separated is Na⁺ and Cl⁻.

Van der Waals forces, also known as Dispersion forces, are the weakest type of molecular bonds. They are only formed through residual molecular attractions when molecules pass by each other. It doesn't even last long due to the uneven electron dispersion. It can be made stronger by adding more electrons in the molecule. This kind of molecular bonds appear in non-polar molecules such as carbon dioxide.

HOPE THIS HELPS!!!!!!!!!!!!!!

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The change that Hydrogen Bonds are most likely responsible for would be:

B). Causes salts to quickly dissolve in water.

As per the details provided, the hydrogen bonds are classified into the category of Van der Waals forces and the primary reason behind this has been that it leads salt to solvate immediately in the water. Amongst all the bonds, covalent bonds are characterized as the toughest while ionic bonds and hydrogen bonds are followed by it in terms of strength.The reason for which hydrogen bonds cause the change of allowing salts to dissolve immediately is that it illustrates a weaker strength of molecules due to its formation with residual uneven construction.

Thus, option B is the correct answer.

Learn more about 'Covalent Bonds' here:

brainly.com/question/10777799

3rd Answer. Rays reflect in random directions

C.Light that bounces off a smooth surface bounces down and back up.

But, an irregular surface, for every bump, the light bounces down up down up down up.

In conclusion, C is the best answer.

I hope this helped! +*♡

Are frequency and wavelength the same thing? No, they are not the same but each is mathematically related to the other. Effectively, the wavelength is the distance between one wave peak and the next wave peak, or in other words, the distance between one wave high point and the next high point. Alternatively it could of course be said that wavelength is the distance between one wave low point and the next wave low point, but lets not get pedantic about it.

Think of waves in the ocean where a person may be observing the top of one wave and the top of the next wave. The wavelength is the distance between these two wave tops, or peaks. With waves in the ocean, the frequency of the waves will be the number of times that a wave peak crosses any given point on the ocean. It is probably easiest to measure frequency of waves from the ocean by standing on the beach and counting how many waves come up on the sand relative to any given time frame. Frequency is typically measured in how many waves per second but with ocean waves we are better to measure how many waves per minute because naturally the frequency will be less than one per second.

There is actually quite a bit of science over how ocean waves travel around our planet because high and low tide in the ocean are created by the moon. There is a theory that the moon creates waves that have a wavelength equal to half of the circumference of planet Earth. This is because there is a high tide at Earths point that is closest to the moon and then another high point that is at the greatest distance from the moon. The problem is that to keep up with the moon one needs to travel around the Earths equator at about 1800 kph, which is impractical for an ocean wave because they quite simply cannot travel at that fast a speed or velocity (technically angular velocity). This is what causes ocean waves to become so messy at times.

When discussing waves, most people are most comfortable discussing electromagnetic waves because almost all communication systems relied on in modern society are based on these waves and their frequency. When collecting electromagnetic waves, like TV waves, for example, there are several components to the antenna. One of them will typically have a loop of metal, which is where the required energy waves (carrying the required signal) are picked up or collected by the antenna. Don’t worry about the other components of the antenna because most are there simply to remove unwanted background waves that may spoil the quality of the signal that we collect. With the TV antenna, the distance across this “collection loop” is the wavelength that the antenna is tuned to collect.

The reason for a loop on the piece of metal that collects TV waves, rather than using a straight piece of wire, is so that all wavelengths that are close to the required one, will be collected. To get slightly more technical, in modern systems we have “frequency modulation”, which is what FM stand for. This means we deliberately make minor adjustments to the precise frequency, but I better not go into that.

The frequency of a TV wave that is being collected is the number of times in any time frame, that a wave front or wave peak, will cross the collection point. With typical electromagnetic waves like TV waves, we use a frequency that is measured to be so many Hertz. The Hertz is the standard measure of such things and it is equal to a number of wavelengths per second. The reason for this is that electromagnetic waves travel at the speed of light, which is incredibly fast.

If we are talking in the old fashioned “long wave” AM radio waves, then the wavelength is often several hundred metres in length. In Melbourne, Australia, the nearest large city to my home, the government owned ABC used a frequency of 774 kHz for many decades. They still do in fact, although most people tuned in probably rely on a repeater station these days and these will broadcast in a higher frequency. 774 kHz is a frequency of 774 thousand cycles per second. This sounds like a high frequency when compared to most other waves, even sound waves, yet because radio waves travel so fast, the wavelength is slightly greater than 387 metres in wavelength, which is almost 424 yards in wavelength.

When comparing wavelength to frequency, one is the inverse of the other so this means that the higher the frequency, the shorter the wavelength, with the rate of travel (velocity) being the factor that determines what sort of figures we come up with when comparing one to the other.
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