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2 years ago

8

Please help for brainliest Don’t skip and don’t answer if u don’t know.

1 answer:

Rainbow [258]2 years ago

8 0

Answer:

burning wood be a chemical change because it wouldn’t be able to go back to its original form. A physical change would be a broken pencil. The pencil is still a pencil, it’s just a physical change.But if it were burned it would be a chemical change.

Explanation:

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Which one is denser? question 2 options: the earth (a solid object) the sun, which is about 300,000 times more massive than the

tankabanditka [31]

The Earth, Mars or Jupiter should be denser than the Sun. Density is defined by mass and volume — components of object or matter. Although the sun is huge, it’s component is made up of mostly gas (hydrogen and helium). While Earth, though smaller than the Sun, contains heavier elements such as iron, sulfur, rocks, sediments, granite, basalt and water. Mars (composed of rocks and nutrients) and Jupiter (contains gases and compounds) as well are denser when compared to the Sun’s density. Referencing to our basic understanding of matter: solid and liquid should be heavier than gas.

6 0

3 years ago

Phthalates used as plasticizers in rubber and plastic products are believed to act as hormone mimics in humans. The value of ΔHc

jeka94

Answer:

$T_f$ = 25.05°C

Explanation:

Given:

the value of ΔHcomb (heat of combustion) for dimethylphthalate (C10H10O4) is = 4685 kJ/mol.

mass = 0.905g of dimethylphthalate

molar mass = 194.18g dimethylphthalate

number of moles of dimethylphthalate = ???

$T_i$ = 21.5°C

$C_{calorimeter}$ = 6.15 kJ/°C

$T_f$ = ???

since we have our molar mass and mass of dimethylphthalate ;we can determine the number of moles as;

0.905g of dimethylphthalate × $\frac{1 mole (dimethylphthalate)}{194.184g(dimethylphthalate)}$

number of moles of dimethylphthalate = 0.000466 moles

Heat released = moles of dimethylphthalate × heat of combustion

= 0.000466 moles × 4685 kJ

= 21.84 kJ

∴ Heat absorbed by the calorimeter = $C_{calorimeter}$ $(T_f-T_i} )$

21.84 kJ =6.15 kJ/°C $* (T_f-21,5^0C)$

21.84 KJ = $(6.15 kJ/^0C * T_f) - (6.15 kJ/^0C*21.5^0C)$

21.84 KJ = $(6.15 kJ/^0C * T_f)$ - 132.225 kJ

21.84 KJ + 132.225 kJ = $(6.15 kJ/^0C * T_f)$

154.065 kJ = $(6.15 kJ/^0C * T_f)$

$T_f$ = $\frac{154.065kJ}{6.15kJ/^0C}$

$T_f$ =25.05°C

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3 years ago

Explain vapour pressure and surface tension What is plasma

worty [1.4K]

Vapor Pressure: Measures how a substance is likey to evaporate

Surface Tension: is the attraction between liquid molecules.

Plasma: is an organic and inorganic substance that is typically found in blood

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3 years ago

How many milliliters of a 8.20 m licl solution contain 18.4 g of licl?

Dovator [93]

Your final answer is that you will need 52.9mL of the 8.20 M of LiCl

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3 years ago

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Anestetic [448]

<span>acceleration I think.</span>

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3 years ago

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