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2 years ago

Can someone please help me:( please dont scroll create 2 quantitative observations

Chemistry

1 answer:

shusha [124]2 years ago

7 0

Answer:

a quantitative observation implies that the subject can be measured by quantity, aka amount or in numbers.

Ex 1: adding one gram of salt to one gram of sugar makes two grams of seasoning. in this example, there are individual quantities (1 gram of each) and total quantity (2 grams). this only changes if the substances have a chemical reaction, such as one of them destroying the other, then the weight would change.

Ex 2: a more simple example is the weight of something. putting the substance on a scale (one specifically for whatever you are measuring, whether it be liquid or solid) is the best way to determine its quantity.

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What is the Definition of "Folded Mountain" in science terms?

just olya [345]

Fold mountains are mountains that form mainly by the effects of folding on layers within the upper part of the Earth's crust. Before either plate tectonic theory developed, or the internal architecture of thrust belts became well understood, the term was used for mostmountain belts, such as the Himalayas.

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3 years ago

Three 1.0-l flasks, maintained at 308 k, are connected to each other with stopcocks. initially the stopcocks are closed. one of

Licemer1 [7]

Answer:

0.6103 atm.

Explanation:

We need to calculate the vapor pressure of each component after the stopcocks are opened.

Volume after the stopcocks are opened = 3.0 L.

1) For N₂:

P₁V₁ = P₂V₂

P₁ = 1.5 atm & V₁ = 1.0 L & V₂ = 3.0 L.

P₂ of N₂ = P₁V₁ / V₂ = (1.5 atm) (1.0 L) / (3.0 L) = 0.5 atm.

2) For H₂O:

Pressure of water at 308 K is 42.0 mmHg.

we need to convert from mmHg to atm: (1.0 atm = 760.0 mmHg).

P of H₂O = (1.0 atm x 42.0 mmHg) / (760.0 mmHg) = 0.0553 atm.

We must check if more 2.2 g of water is evaporated,

n = PV/RT = (0.0553 atm) (3.0 L) / (0.082 L.atm/mol.K) (308 K) = 0.00656 mole.

m = n x cmolar mass = (0.00656 mole) (18.0 g/mole) = 0.118 g.

It is lower than the mass of water in the flask (2.2 g).

3) For C₂H₅OH:

Pressure of C₂H₅OH at 308 K is 102.0 mmHg.

we need to convert from mmHg to atm: (1.0 atm = 760.0 mmHg).

P of C₂H₅OH = (1.0 atm x 102.0 mmHg) / (760.0 mmHg) = 0.13421 atm.

We must check if more 0.3 g of C₂H₅OH is evaporated,

n = PV/RT = (0.13421 atm) (3.0 L) / (0.082 L.atm/mol.K) (308 K) = 0.01594 mole.

m = n x molar mass = (0.01594 mole) (46.07 g/mole) = 0.7344 g.

It is more than the amount in the flask (0.3 g), so the pressure should be less than 0.13421 atm.

We have n = mass / molar mass = (0.30 g) / (46.07 g/mole) = 0.00651 mole.

So, P of C₂H₅OH = nRT / V = (0.00651 mole) (0.082 L.atm/mole.K) (308.0 K) / (3.0 L) = 0.055 atm.

So, total pressure = P of N₂ + P of H₂O + P of C₂H₅OH = 0.5 atm + 0.0553 atm + 0.055 atm = 0.6103 atm.

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3 years ago

Chemical bonds

aniked [119]

Chemical bonds hold atoms together to form compounds through the sharing of electrons or the transferring of electrons.
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3 years ago

Read 2 more answers

!!!Need answer for chem homework ASAP PLS !!!!

stealth61 [152]

Answer:

The answer to your question is: kc = 6.48

Explanation:

Data

Given Molecular weight

CaO = 44.6 g 56 g

CO₂ = 26 g 44 g

CaCO₃ = 42.3 g 100 g

Find moles

CaO 56 g ---------------- 1 mol

44.6 g -------------- x

x = (44.6 x 1) / 56 = 0.8 mol

CO₂ 44 g ----------------- 1 mol

26 g ---------------- x

x = (26 x 1 ) / 44 = 0.6 moles

CaCO₃ 100 g --------------- 1 mol

42.3g -------------- x

x = (42.3 x 1) / 100 = 0.423 moles

Concentrations

CaO = 0.8 / 6.5 = 0.12 M

CO₂ = 0.6 / 6.5 = 0.09 M

CaCO₃ = 0.423 / 6.5 = 0.07 M

Equilibrium constant = $\frac{[products]}{[reactants]}$

Kc = [0.07] / [[0.12][0.09]

Kc = 0.07 / 0.0108

kc = 6.48

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3 years ago

For the reaction N2 + 3H2 = 2NH3, if you have 2.00 moles of N2 and 4.00 moles of H2 : a. Identify the limiting reactant. _______

EastWind [94]

Answer:

The answer to your question is below

Explanation:

For the reaction N2 + 3H2 = 2NH3, if you have 2.00 moles of N2 and 4.00 moles of H2 : a. Identify the limiting reactant. ____________

N2 + 3H2 = 2NH3

1 mol 3 moles 2 moles

Given 2 moles 4 moles

Rule of three for N2

x = (2 x 3) / 1 = 6 mol of H2, it means that is needed 6 moles of H2 and there are only 4, so the limiting reactant is H2

b. How many moles of NH3 can be formed? ____________

rule of three

3 moles of H2 --------------------- 2 moles of NH3

4 moles of H2 --------------------- x

x = (4x2)/3 = 2.7 moles of NH3 are formed

c. How many moles of the excess reactant will remain? _________

x = (4 x 1) / 3 = 1.33

Excess reactant = 2 - 1.33 = 0.67 moles

5 0

4 years ago