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4 years ago

Which is a higher concentration, 10^-9M OR 10^-8M? Explain.

1 answer:

8 0

10^-8 is 10x more Molar than 10^-9, because of the exponents so it’d be 10x more concentrated than 10^-9. The answer is 10^-8.

You might be interested in

What would happen to the ecosystem if there were no nitrogen-fixing bacteria

Gre4nikov [31]

Essentially all the available nitrogen for life in the form of nitrates and ammonia would eventually disappear. Nitrogen is needed to make proteins and other chemicals so it is required for all life to exist. It gets recycled so it would take many decades in most places before the available nitrogen ran out. Many crops like beans depend on it. Humans can manufacture it but it would be hard on the ecosystems of the world and eventually probably lead to the extinction of all the ecosystems of the world.

Hope this helps!

4 0

3 years ago

What volume of carbon dioxide (CO2) will be produced if 2.90 moles of it on (Fe) is produced?

dolphi86 [110]

Answer:

= 97.44 Liters at S.T.P

Explanation:

The reaction between Iron (iii) oxide and Carbon monoxide is given by the equation;

Fe2O3(s)+ 3CO(g) → 3CO2(g) + 2Fe(s)

From the reaction when the reactants react, 2 moles of Fe and 3 moles of CO2 are produced.

Therefore; Mole ratio of Iron : Carbon dioxide is 2:3

Thus; Moles of Carbon dioxide = (2.9/2)×3

= 4.35 moles

But; 1 mole of CO2 at s.t.p occupies 22.4 liters

Therefore;

Mass of CO2 = 22.4 × 4.35 Moles

= 97.44 L

6 0

3 years ago

When 60 mL of 0.22 M NH4Cl is added to 60 mL of 0.22 M NH3, relative to the pH of the 0.10 M NH3 solution the pH of the resultin

densk [106]

Answer:

Will be more acidic

Explanation:

The equilibrium of NH3 in water is:

NH3(aq) + H2O(l) ⇄ NH4⁺(aq) + OH⁻(aq).

Where equilibrium constant, Kb, is:

Kb = 1.85x10⁻⁵ = [NH4⁺] [OH⁻] / [NH3]

From 0.10M NH3, the reaction will produce X of NH4⁺ and X of OH⁻ and Kb will be:

1.85x10⁻⁵ = [X] [X] / [0.10M]

1.8x10⁻⁶ = X²

X = 1.34x10⁻³ = [OH⁻]

As pOH = -log[OH⁻] = 2.87

And as pH = 14 - pOH

pH of the 0.10M NH3 is 11.13

Now, to find the pH of the NH4Cl and NH3 we need to use H-H equation for bases:

pOH = pKb + log [NH4⁺] / [NH3]

Where pKb is -log Kb = 4.74 and [] are moles of both compounds.

Moles of [NH4⁺] = [NH3] = 60mL, 0.060L*0.22M = 0.0132moles:

pOH = 4.74 + log [0.0132] / [0.0132]

pOH = 4.74

pH = 14 - 4.74 = 9.26

That means the pH of the resulting solution will be more acidic

7 0

3 years ago

In a classroom which comparison would a teacher most likely use for describing a mole

irina [24]

Mole - one of the most important concepts in chemistry - is a kind of link to go from the microworld of atoms and molecules in a normal macrocosm grams and kilograms.
In chemistry often have to consider large numbers of atoms and molecules. For fast and efficient calculation made using the weighing method. But it is necessary to know the weight of individual atoms and molecules. In order to identify the molecular weight must be added the weight of all atoms in the compound.

3 0

3 years ago

Determine the full electron configurations: 1. K+ (Z=19) 2. Zn2+ (Z=30)

mixas84 [53]

Answer:

1= K⁺= (Z=19) = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s⁰

2 = Zn²⁺= (Z = 30) =1s² 2s² 2p⁶ 3s² 3p⁶ 4s⁰, 3d¹⁰

Explanation:

When an atom lose or gain the electron ions are formed. There are two types of ions cation and anion.

Cation are formed when atom lose the electron.

Anion are formed when an atom gain the electron.

In given question potassium loses its valance electron and form K⁺ cation. Thus its electronic configuration will be written as,

₁₉K⁺ = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s⁰

While the electronic configuration of potassium in neutral form is:

₁₉K = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹

The atomic number of zinc is 30 and its electronic configuration is:

₃₀Zn= 1s² 2s² 2p⁶ 3s² 3p⁶ 4s², 3d¹⁰

When zinc atom loses its 2 valance electrons the electron configuration will be,

₃₀Zn²⁺= 1s² 2s² 2p⁶ 3s² 3p⁶ 4s⁰, 3d¹⁰

7 0

3 years ago