What is the range for the following set of scores? Scores:6, 12, 9, 17, 11, 4, 14

In this thermochemical reaction, what does the coefficient ½ represent?

timurjin [86]

A thermochemical reaction is a chemical reaction with an additional information of the heat of reaction. For example, this is the thermochemical reaction for the combustion of hydrogen gas:

H₂ (g) + 1/2 O₂ (g) → H₂O (l) ΔH = -285.8 kJ

The coefficient 1/2 represents the number of moles of O₂ needed to combust 1 mole of H₂ gas in order to yield one mole of water.

3 0

4 years ago

Lithium has two stable isotopes with masses of 6.01512 amu and 7.01600 amu. The average molar mass of Li is 6.941 amu. What is t

Dvinal [7]

Answer : The percent abundance of Li isotope-1 and Li isotope-2 is, 6.94 % and 93.1 % respectively.

Explanation :

Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.

Formula used to calculate average atomic mass follows:

$\text{Average atomic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i$ .....(1)

Let the fractional abundance of Li isotope-1 be 'x' and the fractional abundance of Li isotope-2 will be '100-x'

For Li isotope-1 :

Mass of Li isotope-1 = 6.01512 amu

Fractional abundance of Li isotope-1 = x

For Li isotope-2 :

Mass of Li isotope-2 = 7.01600 amu

Fractional abundance of Li isotope-2 = 100-x

Average atomic mass of Li = 6.941 amu

Putting values in equation 1, we get:

$6.941=[(6.01512\times x)+(7.01600\times (100-x))]$

By solving the term 'x', we get:

$x=694.048$

Percent abundance of Li isotope-1 = $\frac{694.048}{100}=6.94\%$

Percent abundance of Li isotope-2 = 100 - x = 100-6.94 = 93.1 %

6 0

3 years ago

Why do larger gases such as Neon produce more color bands (line spectra) than smaller gases like Hydrogen?

LekaFEV [45]

Larger gases produces more spectral lines than the smaller gases because they have more orbitals in their atoms.
Hydrogen has only one orbital in which an electron orbits. At the excited state, that is, when the electron gains energy, the number of energy level it can transcend is very few. For larger elements, they have more orbitals and when excited, they can move from the ground state to other energy levels at which they produce various unique spectral lines.

7 0

3 years ago

HELP ASAP 50-50 CHANCE

docker41 [41]

Answer: The answer is A, A new element or different atom formed from the original two.

Hope this helps! :D

-<em>TanqR</em>

4 0

4 years ago

A compound is broken down by chemical means during

alexandr1967 [171]

Answer : Option 3) Electrolysis.

Explanation : In the process of electrolysis, decomposition of the chemical is done by passing the electric current from the liquid or the solution containing ions in it. This is the process where compound is broken into ions namely, cations and anions.

Rest all options does not involves chemical decomposition of the compound.

Chromatography is a technique where rates of solute and solvent are compared in a medium where the solute components move at different rates and the separation is obtained.

Distillation simply purifies the liquid or solution by heating or cooling process.

Filtration just involves removal of impurities by using a more porous material device to get purified compound.

6 0

3 years ago

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