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3 years ago

State the modern periodic law

Chemistry

2 answers:

avanturin [10]3 years ago

6 0

Answer:

The modern periodic law states that the physical and chemical properties of the elements are the periodic function of the atomic numbers and electronic configurations. ... This repetition occurs if the arrangement of the elements is in order of their increasing atomic numbers.

IRISSAK [1]3 years ago

3 0

Answer:

<h2>the physical and chemical properties of elements are a periodic functions of their atomic numbers.</h2>

<h2>Thank you </h2>

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A gas occupies 50.0mL at a standard temp. What volume would it occupy at 335 Celsius with

tino4ka555 [31]

Answer:

V₂ = 111.3 mL

Explanation:

Given data:

Initial volume of gas = 50.0 mL

Initial temperature = standard = 273.15 K

Final volume = ?

Final temperature = 335 °C (335+273.15 = 608.15 K)

Solution:

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

V₂ = V₁T₂/T₁

V₂ = 50.0 mL ×608.15 K / 273.15 k

V₂ = 30407.5 mL.K / 273.15 K

V₂ = 111.3 mL

7 0

3 years ago

To determine the mass of CO2 that forms from a given mass of CaCO3, which of the following must be known? Check all that apply.

ZanzabumX [31]

To determine the mass of CO₂, the following must be known :

the molar mass of CaCO₃
the mole ratio of CaCO₃ to CO₂
the molar mass of CO₂

<h3>Further explanation</h3>

Reaction

Decomposition of CaCO₃

CaCO₃ ⇒ CaO + CO₂

Given the mass of CaCO₃, so to determine the mass of CO₂ :

1. Find the mol of CaCO₃ from the molar mass of CaCO₃

$\tt n_{CaCO_3}=\dfrac{mass~CaCO_3}{MW~CaCO_3}$

2. Find the mole ratio of CaCO₃ : CO₂(from equation = 1 : 1)

$\tt n_{CaCO_3}\div n_{CO_2}=1\div 1$

3. Find the mass of CO₂ from the molar mass of CO₂

$\tt mass_{CO_2}=n_{CO_2}\times MW_{CO_2}$

3 0

3 years ago

Read 2 more answers

What is S for the reaction N2(g) +O2(g) 2NO? Use G = 173.3 kJ at 303.0 K and H = 180.7 kJ. Use G = H – TS.

Rashid [163]

Given information :

G = 173.3 KJ

H = 180.7 KJ

T = 303.0 K

S = unknown (?)

By using the given formula : G = H - TS , we can calculate the value of 'S'

On rearranging the formula we get : S = $\frac{H-G}{T}$

Plug in the value of G , H and T in the above formula :

S = $\frac{(180.7 KJ - 173.3KJ)}{303.0K}$

S = 0.02442 $\frac{KJ}{K}$

4 0

4 years ago

Read 2 more answers

50 mL of 0.1 M acetic acid is mixed with 50 mL of 0.1 M sodium acetate (the conjugate base). The Ka of acetic acid is approximat

trapecia [35]

Answer:

4.76

Explanation:

In this case, we have to start with the <u>buffer system</u>:

$CH_3COOH~->~CH_3COO^-~+~H^+$

We have an acid ( $CH_3COOH$ ) and a base ( $CH_3COO^-$ ). Therefore we can write the <u>henderson-hasselbach reaction</u>:

$pH~=~pKa+Log\frac{[CH_3COO^-]}{[CH_3COOH]}$

If we want to calculate the pH, we have to <u>calculate the pKa</u>:

$pH=-Log~Ka=4.76$

According to the problem, we have the <u>same concentration</u> for the acid and the base 0.1M. Therefore:

$[CH_3COO^-]=[CH_3COOH]$

If we divide:

$\frac{[CH_3COO^-]}{[CH_3COOH]}~=~1$

If we do the Log of 1:

$Log~1=~zero$

So:

$pH~=~pKa$

With this in mind, the pH is 4.76.

I hope it helps!

8 0

3 years ago

Each molecule of lycopene contains 40 atoms of carbon (plus other atoms). The mass percent of carbon in lycopene is 84.49%. What

IrinaK [193]

Answer: 568g/mol

Explanation:

It should be noted that there are 40 atoms of carbon in lycopene.

Since mass of 1 carbon = 12g/mol

Mass of 40 carbon atoms = 40 × 12g/mol = 480g/mol

Let the molar mass of lycopene be represented by x.

Therefore the molar mass of carbon = x × mass percent of carbon in lycopene

x × 84.49% = 480g/mol

x × 0.8449 = 480g/mol

x = 480/0.8449

x = 568g/mol

The molar mass of lycopene is 568g/mol

5 0

3 years ago

State the modern periodic law​

State the modern periodic law