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3 years ago

Which scientist established the law of octaves?

2 answers:

7 0

J.A.R. Newlands established this in 1885, this describes the <span>chemical elements are arranged according to increasing atomic weight.</span>

laiz [17]3 years ago

6 0

He was an english scientist named john newlands

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if you see a dark mass similar to a blown-up balloon at the top of a volcano, what type of feature are you most likely viewing

Mnenie [13.5K]

Conventional volcanoes are known to erupt after pressure builds up from new magma flowing into the magma chambers that lie below the vents on the Earth's surface.

6 0

4 years ago

Plz help due tomorrow what are the answers 1-5 will be marked brainliest

lina2011 [118]

1.)D

2.)B

3.)A

4.)C

5.)C

6 0

3 years ago

A chemist fills a reaction vessel with 9.20 atm nitrogen monoxide (NO) gas, 9.15 atm chlorine (CI) gas, and 7.70 atm nitrosyl ch

ivanzaharov [21]

Answer:

The reactions free energy $\Delta G = -49.36 kJ$

Explanation:

From the question we are told that

The pressure of (NO) is $P_{NO} = 9.20 \ atm$

The pressure of (Cl) gas is $P_{Cl} = 9.15 \ atm$

The pressure of nitrosly chloride (NOCl) is $P_{(NOCl)} = 7.70 \ atm$

The reaction is

$2NO_{(g)} + Cl_2 (g)$ ⇆ $2 NOCl_{(g)}$

From the reaction we can mathematically evaluate the $\Delta G^o$ (Standard state free energy ) as

$\Delta G^o = 2 \Delta G^o _{NOCl} - \Delta G^o _{Cl_2} - 2 \Delta G^o _{NO}$

The Standard state free energy for NO is constant with a value

$\Delta G^o _{NO} = 86.55 kJ/mol$

The Standard state free energy for $Cl_2$ is constant with a value

$\Delta G^o _{Cl_2} = 0kJ/mol$

The Standard state free energy for $NOCl$ is constant with a value

$\Delta G^o _{NOCl} =66.1kJ/mol$

Now substituting this into the equation

$\Delta G^o = 2 * 66.1 - 0 - 2 * 87.6$

$= -43 kJ/mol$

The pressure constant is evaluated as

$Q = \frac{Pressure \ of \ product }{ Pressure \ of \ reactant }$

Substituting values

$Q = \frac{(7.7)^2 }{(9.2)^2 (9.15) } = \frac{59.29}{774.456}$

$= 0.0765$

The free energy for this reaction is evaluated as

$\Delta G = \Delta G^o + RT ln Q$

Where R is gas constant with a value of $R = 8.314 J / K \cdot mol$

T is temperature in K with a given value of $T = 25+273 = 298 K$

Substituting value

$\Delta G = -43 *10^{3} + 8.314 *298 * ln [0.0765]$

$= -43-6.36$

$\Delta G = -49.36 kJ$

4 0

3 years ago

Beryllium oxide, Beo, is an electrical insulator. How

egoroff_w [7]

Answer:

There are 10.0 moles of beryllium oxide in a 250 grams sample of the compound.

Explanation:

We can calculate the number of moles (η) of BeO as follows:

$\eta = \frac{m}{M}$

Where:

m: is the mass = 250 g

M: is the molar mass = 25.0116 g/mol

Hence, the number of moles is:

$\eta = \frac{250 g}{25.0116 g/mol} = 10.0 moles$

Therefore, there are 10.0 moles of beryllium oxide in a 250 grams sample of the compound.

I hope it helps you!

3 0

3 years ago

Pls helppp

defon

The heat absorbed to raise temperature : Q = 31350 J

<h3>Further explanation </h3>

Given

m = mass = 150 g

Δt = Temperature difference : 50 °C

Required

Heat absorbed

Solution

Heat can be formulated

The specific heat of water = c = 4.18 J/g °C

Input the value :

Q = 150 x 4.18 x 50

Q = 31350 J

6 0

3 years ago