Match the term (exothermic) with the correct definition.

energy goes into the chemical and cool downs the surrounding area.

energy leaves the chemical and cools down the surrounding area

energy leaves the chemical and heats up the surrounding area

Answer:

Explanation:

Photosynthesis is important to living organisms because it is the number one source of oxygen in the atmosphere. Without photosynthesis, the carbon cycle could not occur, oxygen-requiring life would not survive and plants would die. ... The importance of photosynthesis in our life is the oxygen it produces

#1: A covalent bond

#2 False

#3True

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:

geruow0irghvn3p0unhie0ghik

Explanation:

Answer:

e

Explanation:

it's in the index fossil range

Answer:

Explanation:

In marine strata, index fossils that are commonly used include the single-celled Protista with hard body parts and larger forms such as ammonoids. In terrestrial sediments of the Cenozoic Era, which began about 65.5 million years ago, mammals are widely used to date deposits.

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.

The intial temperature : 59.865 °C

Heat added :

Q = m . c . ΔT

Q = heat, J  

m = mass, g  

c = specific heat, joules / g ° C  

∆T = temperature difference, ° C / K  

[tex]\tt 305=94.8\times 0.128\times (85-t_1)\\\\85-t_1=25.135\\\\t_1=59.865^oC[/tex]

Answer:

B

Explanation:

Boron has 5 protons.

Because the deep roots of big trees hold the soil and don't let it slip away simply by rain or wind.

Answer:

the roots of the trees keep the soil in place opposed to a barren landscape that has little to no plants to keep the soil in place

hope this helps (╹ڡ╹ )

Answer:

"Low levels of the hormone epinephrine, also called adrenaline, cause blood vessels to relax and widen. High levels of this same hormone, along with the hormone norepinephrine, cause the blood vessels to narrow and the heart rate to rise, increasing blood pressure."

Explanation:

Answer:

1

Explanation:

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: 7 neutrons

Explanation: Atomic number refers to the number of protons in the nucleus of the atom. Also you can treat atomic mass as how many particles (protons and neutrons) are in the nucleus of the atom. So for this problem:

14 particles - 7 protons = 7 neutrons (and we know all that's left over is neutrons because we subtracted all the protons)

Answer: C

Explanation:

There are 761.4 grams of CS2 in 10.00 mol.

To calculate the amount of grams present in a given amount of moles, the molar mass of the substance must be used, as follows:

                                        [tex]m = MM \times mol[/tex]

In this way, just perform the following operation:

                                          [tex]m = 76.14 \times 10[/tex]

                                         [tex]m = 761.4 grams[/tex]

Thus, there are 761.4 grams of CS2 in 10 mol of the substance.

Learn more about mole calculation in: brainly.com/question/15693285

Answer:

Explanation:

The acceleration of an object given it's mass and the force acting on it can be found by using the formula

[tex]a = \frac{f}{m} \\ [/tex]

f is the force

m is the mass

From the question we have

[tex]a = \frac{47}{7} \\ = 6.714285...[/tex]

We have the final answer as

Hope this helps you

Answer:

J electrons

Explanation:

Electrons are the negatively charged subatomic particles that surrounds the nucleus of an atom.

Answer:

sodium

Explanation:

it is an alkali metal

Answer:

02- i think your welcome hope it helps

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

Explanation:

The flame test is used to visually determine the identity of an unknown metal or metalloid ion based on the characteristic color the salt turns the flame of a Bunsen burner. The heat of the flame excites the electrons of the metals ions, causing them to emit visible light

Answer:

Theoretical yield = 16.76 g

Percent yield = 87%

Explanation:

Given data:

Mass of iron oxide = 23.5 g

Theoretical yield of iron = ?

Actual yield of iron = 14.5 g

Percent yield of iron = ?

Solution:

Chemical equation:

2Fe₂O₃ + 3C     →  4Fe + 3CO₂

Number of moles of iron oxide:

Number of moles = mass/molar mass

Number of moles = 23.5 g/ 159.69 g/mol

Number of moles = 0.15 mol

Now we will compare the mole of iron oxide with iron metal.

                      Fe₂O₃         :            Fe

                         2              :              4

                      0.15            :          4/2×0.15 = 0.3

Mass of iron:

Mass = number of moles × molar mass

Mass = 0.3 mol × 55.85 g/mol

Mass = 16.76 g

Percent yield:

percent yield = (actual yield / theoretical yield)× 100

Percent yield = (14.5 g / 16.76 g) × 100

Percent yield = 0.87 × 100

Percent yield = 87%

Answer:

I tried the answer above and it’s correct

Explanation:

Answer:

fewer collisions occur between particles or lowering the temperature

Explanation:

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:

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:

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:

there are two significant figures

Explanation:

Answer:

there are two

Explanation:

because the zeros dont count

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

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: