Explanation:
An observation that can be counted is known as quantitative observation. On the other hand, an observation that does not contain any numerical data is known as non-quantitative observation.
Therefore, given observations are classified as follows.
(a) The Sun rises in the east - It is a non-quantitative observation as it cannot be measured.
(b) A person weighs one-sixth as much on the Moon as on Earth - It is a quantitative observation as it can be measured because we know the mass of moon. Hence, we can find out the weight of person.
(c) Ice floats on water - It is a non-quantitative observation as it cannot be measured.
(d) A hand pump cannot draw water from a well more than 34 ft deep _ It is a quantitative observation because it is measure that more than 34 ft deep water cannot be drawn by the pump.
1) V(CH₄) = 0,376 L.T(CH₄) = 304 K.p(CH₄) = 1,5 atm 101325 Pa/atm = 151987,5 Pa = 151,9875 kPa.R = 8,314 J/K·mol.Use ideal gas law: p·V = n·R·T.n(CH₄) = p · V ÷ R · T.n(CH₄) = 151,9875 kPa · 0,376 L ÷ 8,314 J/K· mol · 304 K.n(CH₄) = 0,0226 mol.V(CH₄) = n(CH₄) · Vm.V(CH₄) = 0,0226 mol · 22,4 dm³/mol.V(CH₄) = 0,506 dm³ = 0,506 L.
2) V(SO₂) = 5,2 L.p(SO₂) = 45,2 atm = 45,2 atm · 101,325 kPa/atm = 4579,89 kPa.T(SO₂) = 293 K.R = 8,314 J/K·mol.Use ideal gas law: p·V = n·R·T.n(SO₂) = p · V ÷ R · T.n(SO₂) = 4579,89 kPa · 5,2 L ÷ 8,314 J/K· mol · 293 K.n(CH₄) = 9,77 mol.There is not enogh SO₂, 225 mol - 9,77 mol = 215,23 mol is needed.
3) p(He) = 3,50 atm · 101,325 kPa/atm = 354,63 kPa.V(He) = 4,00 L.n(He) = 0,410 mol.R = 8,314 J/K·mol.Use ideal gas law: p·V = n·R·T.T = p · V ÷ R · n.T(He) = 354,63 kPa · 4,00 L ÷ 8,314 J/K· mol · 0,410 mol.T(He) = 416,14 K.n - amount of substance.
4) p(Ar) = 1,00 atm · 101,325 kPa/atm = 101,325 kPa.V(Ar) = 3,4 L.T(Ar) = 263 K.R = 8,314 J/K·mol.Use ideal gas law: p·V = n·R·T.n(Ar) = p · V ÷ R · T.n(Ar) = 101,325 kPa · 3,4 L ÷ 8,314 J/K· mol · 263 K.n(Ar) = 0,157 mol.n(Ar) = 0,157 mol + 2,5 mol = 2,657 mol.p(Ar) = 2,657 mol · 8,314 J/K· mol · 263 K ÷ 3,4 L.p(Ar) = 1708,74 kPa.
In order for a molecule to exist in a stable bond, the prefered overall charge is neutral. Na is a positive one charge and Cl is negative, therfore it is neutral.
Answer:
For Silver , The heat absorbed = <u>246.75 J</u>
For Copper , The heat is =<u> 343.42 J</u>
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Explanation:
The change in temperature is calculated by:

T2 = 25 C
T1 = 15 C


The energy in Joules can be calculated using :

here , m = mass of the substance
c = the heat capacity
q = heat absorbed / released
We need to calculate the mass , In order to determine the value of "q".
<u>Calculation for Silver :</u>
<u><em>The mass is calculated from the density of the element.</em></u>
density of Silver = 10.5 g/ml (look at the table of density)
Volume of Cube = 10 cm^3 (given)
1 cm^3 = 1 mL
10 cm^3 = 10 mL
The mass can be calculated using the formula:



Insert the value of m , c, T in the equation.
for Silver the value of "c"= 0.235 J/gC (Look at the table)


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<u>Calculation for Copper:</u>
Again first calculate the mass of Copper.
Density of Copper = 8.92 g/ml
Volume = 10 mL



Insert the value of m , c, T in the equation.
for Silver the value of "c"= 0.385 J/gC (Look at the table)


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