All categories

2 years ago

What is a coefficient? What is a subscript?

Chemistry

2 answers:

Katarina [22]2 years ago

8 0

Answer:

The coefficient tells you how many molecules of that substance there is. The subscript tells you what the substance it. It tells you the the amount of each element there are in the molecule. Changing it would change the substance itself.

Ierofanga [76]2 years ago

8 0

Answer:

Explanation:

You might be interested in

How many moles of Manganese there in are 5.76 x 10(15) atoms of Mn?

aksik [14]

Answer:

1. 9.57 × 10^-9 moles.

2. 7.38mol

Explanation:

1.) To find the number of moles there are in the number of particles in an atom, we divide the number of particles (nA) by Avagadro's constant (6.02 × 10^23)

Hence, to find the number of moles (n) of Manganese (Mn), we say:

5.76 x 10^15 atoms ÷ 6.02 × 10^23

5.76/6.02 × 10^(15-23)

= 0.957 × 10^-8

= 9.57 × 10^-9 moles.

2.) Mole = mass/molar mass

Molar mass of sodium chloride (NaCl) = 23 + 35.5

= 58.5g/mol

mole = 431.6 g ÷ 58.5g/mol

mole = 7.38mol

7 0

2 years ago

Definition of isotopes

sukhopar [10]

Isotopes are atoms of the same element that have different numbers of neutrons.

5 0

3 years ago

Read 2 more answers

Which of the following statements about the combustion of glucose with oxygen to form water and carbon dioxide (C6H12O6 + 6 O2 →

worty [1.4K]

Answer:

The correct statement is:

E - The entropy of the products is greater than the entropy of the reactants.

Explanation:

C₆H₁₂O₆ + 6 O₂ → 6 CO₂ + 6 H₂O

As glucose is a large molecule and then it is transformed into many molecules of water and carbon dioxide, the entropy of the system increases. If the number of molecules increases, the disorder increases.

Initial state: 7 molecules (1 glucose + 6 oxygen)

Final state: 12 molecules (6 carbon dioxide + 6 water)

3 0

3 years ago

Read 2 more answers

The activation energy for a reaction is changed from 184 kJ/mol to 59.0 kJ/mol at 600. K by the introduction of a catalyst. If t

11111nata11111 [884]

Answer:

The catalyzed reaction will take 2.85 seconds to occur.

Explanation:

The activation energy of a reaction is given by:

$k = Ae^{-\frac{E_{a}}{RT}}$

For the reaction without catalyst we have:

$k_{1} = Ae^{-\frac{E_{a_{1}}}{RT}}$ (1)

And for the reaction with the catalyst:

$k_{2} = Ae^{-\frac{E_{a_{2}}}{RT}}$ (2)

Assuming that frequency factor (A) and the temperature (T) are constant, by dividing equation (1) with equation (2) we have:

$\frac{k_{1}}{k_{2}} = \frac{Ae^{-\frac{E_{a_{1}}}{RT}}}{Ae^{-\frac{E_{a_{2}}}{RT}}}$

$\frac{k_{1}}{k_{2}} = e^{\frac{E_{a_{2}} - E_{a_{1}}}{RT}$

$\frac{k_{1}}{k_{2}} = e^{\frac{59.0 \cdot 10^{3}J/mol - 184 \cdot 10^{3} J/mol}{8.314 J/Kmol*600 K} = 1.31 \cdot 10^{-11}$

Since the reaction rate is related to the time as follow:

$k = \frac{\Delta [R]}{t}$

And assuming that the initial concentrations ([R]) are the same, we have:

$\frac{k_{1}}{k_{2}} = \frac{\Delta [R]/t_{1}}{\Delta [R]/t_{2}}$

$\frac{k_{1}}{k_{2}} = \frac{t_{2}}{t_{1}}$

$t_{2} = t_{1}\frac{k_{1}}{k_{2}} = 6900 y*1.31 \cdot 10^{-11} = 9.04 \cdot 10^{-8} y*\frac{365 d}{1 y}*\frac{24 h}{1 d}*\frac{3600 s}{1 h} = 2.85 s$

Therefore, the catalyzed reaction will take 2.85 seconds to occur.

I hope it helps you!

4 0

3 years ago

A sample of a pure compound that weighs 60.3 g contains 20.7 g Sb (antimony) and 39.6 g F (fluorine). What is the percent compos

Volgvan

Answer:

The percent composition of fluorine is 65.67%

Explanation:

Percent Composition is a measure of the amount of mass an element occupies in a compound. It is measured in percentage of mass.

That is, the percentage composition is the percentage by mass of each of the elements present in a compound.

The calculation of the percentage composition of an element is made by:

$percent composition element A=\frac{total mass of element A}{mass of compound} *100$

In this case, the percent composition of fluorine is:

$percent composition of fluorine=\frac{39.6 g}{60.3 g} *100$

percent composition of fluorine= 65.67%

<u><em>The percent composition of fluorine is 65.67%</em></u>

4 0

3 years ago