Balance the combustion reaction between octane and oxygen. 2C8H18 + O2 → CO2 + H2O

some constellations, such ad Ursa Minor, are visible in the sky year-round; other contellations appear for only part of the year

worty [1.4K]

While most constellations are only visible to us in different seasons, some are always there 24/7/365 because they are positioned close to the Polar Axis, or the Polaris.

5 0

2 years ago

Under standard-state conditions, which of the following species is the best reducing agent? a. Ag+ b. Pb c. H2 d. Ag e. Mg2+

eimsori [14]

Answer: The correct answer is Option b.

Explanation:

Reducing agents are defined as the agents which help the other substance to get reduced and itself gets oxidized. They undergo oxidation reaction.

$X\rightarrow X^{n+}+ne^-$

For determination of reducing agents, we will look at the oxidation potentials of the substance. Oxidation potentials can be determined by reversing the standard reduction potentials.

For the given options:

Option a: $Ag^+$

This ion cannot be further oxidized because +1 is the most stable oxidation state of silver.

Option b: $Pb$

This metal can easily get oxidized to $Pb^{2+}$ ion and the standard oxidation potential for this is 0.13 V

$Pb\rightarrow Pb^{2+}+2e^-;E^o_{(Pb/Pb^{2+})}=+0.13V$

Option c: $H_2$

This metal can easily get oxidized to $H^{+}$ ion and the standard oxidation potential for this is 0.0 V

$H_2\rightarrow 2H^++2e^-;E^o_{(H_2/H^{+})}=0.0V$

Option d: $Ag$

This metal can easily get oxidized to $Ag^{+}$ ion and the standard oxidation potential for this is -0.80 V

$Ag\rightarrow Ag^{+}+e^-;E^o_{(Ag/Ag^{+})}=-0.80V$

Option e: $Mg^{2+}$

This ion cannot be further oxidized because +2 is the most stable oxidation state of magnesium.

By looking at the standard oxidation potential of the substances, the substance having highest positive $E^o$ potential will always get oxidized and will undergo oxidation reaction. Thus, considered as strong reducing agent.

From the above values, the correct answer is Option b.

8 0

3 years ago

Identify each of the following solids as molecular, ionic, or atomic.

Kisachek [45]

Answer :

(A) Br₂ (s) : molecular solids

(B) AgCl (s) : ionic solids

(C) S (s) : atomic solids

(D) CH₄ (s) : molecular solids

Explanation :

Molecular solids : It is defined as the solids in which they are held together by covalent forces, dipole interactions as attractive forces etc.

Ionic solids : It is defined as the solids in which the atoms composed with oppositely charged ions.

Atomic solids : It is defined as the solids in which the molecules are held together by covalent forces and also includes pure substance.

(A) Br₂ (s)

It is molecular solids because they are held together by covalent forces.

(B) AgCl (s)

It is ionic solids because in this atoms composed with oppositely charged ions.

(C) S (s)

It is atomic solids because it is a pure substance.

(D) CH₄ (s)

It is molecular solids because they are held together by covalent forces.

7 0

2 years ago

a sample of an oxide of antimony (sb) contain 19.75 g of antimony combine with 6.5 g of oxygen . what is the simplest formula fo

frez [133]

Explanation:

The given data is as follows.

Mass of antimony = 19.75 g

Molar mass of Sb = 121.76 g/mol

Therefore, calculate number of moles of Sb as follows.

Moles of Sb = $\frac{mass}{\text{molar mass}}$

= $\frac{19.75 g}{121.76 g/mol}$

= 0.162 mol

Mass of oxygen given is 6.5 g and molar mass of oxygen is 16 g/mol. Hence, moles of oxygen will be calculated as follows.

Moles of oxygen = $\frac{mass}{\text{molar mass}}$

= $\frac{6.5 g}{16 g/mol}$

= 0.406 mol

Hence, ratio of moles of Sb and O will be as follows

Sb : O

$\frac{0.162}{0.162} : \frac{0.406}{0.162}$

1 : 2.5

We multiply both the ratio by 2 in order to get a whole number. Therefore, the ratio will be 2 : 5.

Thus, we can conclude that the empirical formula of the given oxide is $Sb_{2}O_{5}$ .

4 0

2 years ago

Looking at the following equation, what coefficient should be placed in front of the H2? Fe + H2SO4 --> Fe2(SO4)3 + H2

Hatshy [7]

Answer:

3 (three)

Explanation:

2 Fe + 3H2SO4 = Fe2(SO4)3 + 3 H2 (basically just balance both sides)

6 0

2 years ago