it!
t
Calculate How old was the tree when it was
cut down?

Answer:

1-state what the lab is about, that is, what scientific concept (theory, principle, procedure, etc.) you are supposed to be learning about by doing the lab. You should do this briefly, in a sentence or two. If you are having trouble writing the opening sentence of the report, you can try something like: "This laboratory experiment focuses on X…"; "This lab is designed to help students learn about, observe, or investigate, X…." Or begin with a definition of the scientific concept: "X is a theory that…."                        2-give the necessary background for the scientific concept by telling what you know about it (the main references you can use are the lab manual, the textbook, lecture notes, and other sources recommended by the lab manual or lab instructor; in more advanced labs you may also be expected to cite the findings of previous scientific studies related to the lab). In relatively simple labs you can do this in a paragraph following the initial statement of the learning context. But in more complex labs, the background may require more paragraphs.

Explanation:

Answer: the correct answer is A

Explanation:

Answer:

0.92moles

Explanation:

Given reaction:

              2Fe + 3Cl₂ →  2FeCl₃

Mass of FeCl₃  = 100g

Unknown:

Number of moles of Cl₂  needed = ?

Solution:

To solve this problem, we work from the known specie to the unknown.

From the mass of the FeCl₃ given, we can solve for the number of moles of the unknown.

  Number of moles  = [tex]\frac{mass}{molar mass}[/tex]  

  Molar mass of  FeCl₃ = 56 + 3(35.5) = 162.5g/mol

   Number of moles  = [tex]\frac{100}{162.5}[/tex]  = 0.62mole

From the reaction expression;

           2 mole of FeCl₃ is produced from 3 moles of  Cl₂  

           0.62 mole of FeCl₃ will be produced from [tex]\frac{0.62 x 3}{2}[/tex]   = 0.92mole

The number of moles of Cl₂  = 0.92moles

Answer:

B - What we change

Explanation:

Dependent Variable - What we measure

Control Variable - what stays the same

Conclusion - what we conclude

Hope this can Help!

:D

Answer:

Explanation:

by stoichiometry

nNH3/2=nH2/3

0.25/2=nH2/3

nH2=0.25×3/2

nH2=0.375 mol

so its 0.38 mol

Answer:

I have this quiz rn I will try 0.38 if it is right I’ll edit this and say that

Explanation:

Answer:

Explanation:

before the reaction you have K=2 and Cl=4

after the reaction K=2 and Cl=2 so it does not follow the law of conservation

Answer:

A change in the shape of a substance

Explanation:

Because when ths shape of a sunstance changes , its physical appearance changes .A physical change is a change to the physical—as opposed to chemical—properties of a substance. They are usually reversible. The physical properties of a substance include such characteristics as shape (volume and size), color, texture, flexibility, density, and mass.

Answer:

paper plate

Explanation:

A renuable source is a source that would replenish in ones lifetime. Trees make paper and grow in the span of a average human life.

Answer:

V₂ = 112.14 mL

Explanation:

Given data:

Initial volume = 500 mL

Initial pressure = 270 mmHg (270/760 =0.355 atm)

Initial temperature = 55 °C (55 +273 = 328 K)

Final temperature = 100°C (100+273 = 373 K)

Final volume = ?

Final pressure = 1.8 atm

Formula:  

P₁V₁/T₁ = P₂V₂/T₂  

P₁ = Initial pressure

V₁ = Initial volume

T₁ = Initial temperature

P₂ = Final pressure

V₂ = Final volume

T₂ = Final temperature

Solution:

V₂ = P₁V₁ T₂/ T₁ P₂  

V₂ = 0.355 atm × 500mL × 373 K / 328 K × 1.8 atm

V₂ = 66207.5 atm .mL. K /  590.4 K.atm

V₂ = 112.14 mL

Answer:

The tempreature???

Explanation:

Colder tempreatures lead to a slower chemical reaction and warmer tempreatures lead to a faster  chemical reaction.

Answer:

1 g

Explanation:

The following data were obtained from the question:

Original amount (N₀) = 32 g

Time (t) = 71.5 days

Half-life of phosphorus (t½) = 14.3 days

Amount remaining (N) =?

Next, we shall determine the rate of disintegration. This can be obtained as follow:

Half-life of phosphorus (t½) = 14.3 days

Decay constant (K) =?

K = 0.693 / t½

K = 0.693 / 14.3

K = 0.0485 /day

Finally, we shall determine the amount remaining as illustrated below:

Original amount (N₀) = 32 g

Time (t) = 71.5 days

Decay constant (K) = 0.0485 /day

Amount remaining (N) =?

Log (N₀/N) = Kt/2.303

Log (32/N) = 0.0485 × 71.5 / 2.303

Log (32/N) = 3.46775 / 2.303

Log (32/N) = 1.5058

Take the antilog of 1.5058

32/N = antilog (1.5058)

32/N = 32.05

Cross multiply

32 = N × 32.05

Divide both side by 32.05

N = 32 / 32.05

N = 0.998 ≈ 1 g

Thus, the amount remaining after 71.5 days is approximately 1 g.

The half-life of a radioactive substance refers to the time taken for the substance to Decay to half of its initial size. Hence, the mass of the substance left after 71.5 days is 1 gram.

After 14.3 days ;

After 14.3 × 2 = 28.6 days :

After 14.3 × 3 days = 42.9 days :

After 14.3 × 4 days = 57.2 days :

After 14.3 × 5 days = 71.5 days :

Hence, the mass of the sample left after 71.5 days would be 1 gram.

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Answer:

5 mol

Explanation:

by stoichiometry

nN2/1=nNH3/2

2.5=nNH3/2

nNH3=2.5×2

nNH3= 5 mol

Answer: I got 5.0 moles

Explanation:

Answer:

A.) It cannot be quickly replaced.

Explanation:

Aluminum is extremely useful to humans but is semi-difficult to produce. Because of this, your answer will be numero uno. (Or A.)

Answer:

The screw with 10 wraps is the correct answer

Explanation:

The screw with 6 wraps would create a strong hold.

The strongest member of the family of wood screws is a lag screw. It is a reliable and sturdy fastener that frequently has a square head or an externally powered hex drive.

In general, lag screws are significantly stronger and heavier than standard wood screws. They have a tapered point and coarse threads.

Thus, The screw with 6 wraps would create a strong hold.

To learn more about Screw, refer to the below link:

https://brainly.com/question/24168324

# SPJ5

Answer:

120g

Explanation:

Based on the reaction, when 1 mole of propane and 5 moles of oxygen react, 3 moles of CO2 and 4 moles of H2O are produced. The ratio of production is 3 moles of CO2 per 4 moles of H2O.

Thus, we need to convert mass of water to moles using its molar mass:

Moles H2O (Molar mass: 18g/mol):

63g H2O * (1mol / 18g) = 3.5 moles H2O

Converting to moles of CO2:

3.5 moles H2O * (3 moles CO2 / 4 moles H2O) = 2.625 moles CO2

Mass CO2 (Molar mass: 44g/mol):

2.625 moles CO2 * (44g / mol) = 115.5g of CO2 are released

The chemical equation is said to be balanced if the number of atoms in the reactants and products is the same

Equation balanced ⇒ total number of atoms in reactants(on the left)= total number of atoms in products(on the right)

H₂+O₂---> H₂O

Reactants : H₂, O₂

Products : H₂O

not balanced

H₂O₂ ---> H₂O+O₂

Reactants : H₂O₂

Products : H₂O, O₂

not balanced

Na+O₂ ---> Na₂O

Reactants : Na, O₂

Products :  Na₂O

not balanced

N₂+H₂ ---> NH₃

Reactants : N₂, H₂

Products :  NH₃

not balanced

P₄+O₂---> P₄O₁₀

Reactants : P₄, O₂

Products :  P₄O₁₀

not balanced

Fe+H₂O ----> Fe₃O₄ + H₂

Reactants : Fe, H₂O

Products :  Fe₃O₄

not balanced

Explanation:

Glass is not a liquid in the strictest sense of the word. But it is also not a standard solid. The chemistry of glass is complex and research is ongoing, but the current consensus is that glass is a phase of matter all its own, known as an "amorphous solid". Scientists refer to any amorphous solid as a "glass". Glass transitions are highly complex and cannot be treated in the same way as traditional phase transitions.

Answer:

It's a liquid state before its cooled.

Answer:

i think its 12, but i'm not 100% sure

Explanation:

Answer:

Explanation:

Firstly, it should be noted that melting and freezing points are the same. Thus, when a substance melts at a certain temperature, it means it can also start freezing/solidifying at that same temperature. That been said, when the substance P is a solid at a certain temperature, the other compound Q will boil at that same temperature and hence will be a gas at that same temperature.

If P is solid, it simply means that Q must still be in the liquid state.

From the question, we can see that, the melting point of P and the boiling point of Q are the same. The melting point of a substance is the temperature at which the solid turns to liquid while the boiling point of a substance is the temperature at which a liquid turns to a gas.

If P is solid, it simply means that Q must still be in the liquid state. It has not yet started boiling since the melting point of P and the boiling point of Q are the same.

Learn more: https://brainly.com/question/8553652

Answer:

y  = 13x + 4

Explanation:

Given parameters:

number of computer games bought  = x

cost of each games  = $13

number of a magazine  = 1

cost of magazine  = $4

Unknown:

Total amount of money spent = ?

Solution:

The total amount spent;

  let total amount  = y

 y  = total cost of magazine + total cost of computer games

 total cost of magazine  =$4

 total cost of computer games  = 13x

y  = 13x + 4

Answer:

[tex].5865 \\ \\ \\ \\ \\ \5865[/tex]

[tex] \\ \\ 5865 \inf \inft \cos( \\ \) [/tex]

Answer:

Sound.

Explanation:

Sound requires a medium such as air to travel.

Answer:

fewer collisions occur between particles or lowering the temperature

Explanation:

Answer:

yes

Explanation:

that is the answer

Answer:

Chemistry is the scientific study of the structure of substances, how they react when combined and how they behave under different situations.

Answer:

The branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances.

Explanation:

Hope this helps!!!!!!

:)

Answer:

Greater

Greater

Explanation:

The amplitude of a wave is the height of the wave or the vertical displacement of the wave motion. We determine a wave amplitude usually by looking at the graph of the wave.

Amplitude is directly proportional to the energy of a wave. The higher the amplitude of a wave, the more its energy.

Frequency is the number of waves that passes a point at a particular instance of time. It is also directly proportional to the energy carried by a wave. The higher the frequency of a wave, the greater its energy.

Answer:

b

Explanation:

i looked it up on Google

Answer:the 4th one is incorrect,and the 1st one is incorrect hope this helps.

Adsorption is defined as a process in which gas molecules tend to adsorb on the surface of a solid solvent.

Therefore, the statement solids are not able to act as a solvent if a gas is the solute, is false.

On the other hand, gases can also act as a solvent if a solid is the solute.

Explanation:

Adsorption is defined as a process in which gas molecules tend to adsorb on the surface of a solid solvent.

Therefore, the statement solids are not able to act as a solvent if a gas is the solute, is false.

On the other hand, gases can also act as a solvent if a solid is the solute.For example, air present in the surrounding acts as a solvent and solid substances present in the surrounding acts as a solute.

Hence, the statement gases are not able to act as a solvent if a solid is the solute, is false.

Thus, we can conclude that following are the statements which are incorrect.

Solids are not able to act as a solvent if a gas is the solute.

Gases are not able to act as a solvent if a solid is the solute.

Answer:

there are two significant figures

Explanation:

Answer:

there are two

Explanation:

because the zeros dont count