13. Sodium, Na, shows metallic properties. Identify another element that is likely to show similar metallic properties.

Identify the power of ten that defines each of these prefixes. Input your answers as 10 x where x is the power of ten. nano- ___

Gemiola [76]

Answer: The quantity of every prefix is written below as a power of ten.

Explanation:

In the metric system of measurement, the name of multiples and subdivision of any unit is done by combining the name of the unit with the prefixes.

For Example: deka, hecto and kilo means 10, 100 and 1000 respectively. Deci, centi and milli means one-tenth, one-hundredth, and one-thousandth respectively.

The quantity of these prefixes are written as the power of 10.

For the given prefixes:

Nano: The quantity will be $10^{-9}$

Kilo: The quantity will be $10^3$

Centi: The quantity will be $10^{-2}$

Micro: The quantity will be $10^{-6}$

Milli: The quantity will be $10^{-3}$

Mega: The quantity will be $10^6$

Hence, the quantity of every prefix is written above as a power of ten.

7 0

4 years ago

When 18.0 mL of a 8.43×10-4 M cobalt(II) fluoride solution is combined with 22.0 mL of a 9.72×10-4 M sodium hydroxide solution d

Eva8 [605]

Answer:

Q = 1.08x10⁻¹⁰

Yes, precipitate is formed.

Explanation:

The reaction of CoF₂ with NaOH is:

CoF₂(aq) + 2 NaOH(aq) ⇄ Co(OH)₂(s) + 2 NaF(aq).

The solubility product of the precipitate produced, Co(OH)₂, is:

Co(OH)₂(s) ⇄ Co²⁺(aq) + 2OH⁻(aq)

And Ksp is:

Ksp = 3x10⁻¹⁶= [Co²⁺][OH⁻]²

Molar concentration of both ions is:

[Co²⁺] = 0.018Lₓ (8.43x10⁻⁴mol / L) / (0.018 + 0.022)L = 3.79x10⁻⁴M

[OH⁻] = 0.022Lₓ (9.72x10⁻⁴mol / L) / (0.018 + 0.022)L = 5.35x10⁻⁴M

Reaction quotient under these concentrations is:

Q = [3.79x10⁻⁴M] [5.35x10⁻⁴M]²

Q = 1.08x10⁻¹⁰

As Q > Ksp, the equilibrium will shift to the left producing Co(OH)₂(s) the precipitate

8 0

4 years ago

What do I scan to confirm that a book is relevant and valuable as a source

Elden [556K]

It's genre. Look for something either on a final or starting page near the cover, and check to look if it's non fiction, or anything else that could prove it as reliable.

7 0

3 years ago

b) 2C2H2(g) + 5O2(g)⟶4CO2(g) + 2H2O(l) 6.54 Calculate the heats of combustion for the following reactions from the standard enth

IRINA_888 [86]

Answer:

a. ΔH⁸ = -1420 kJ/mol b. ΔH⁸ = -1144.84 kJ/mol

Explanation:

a.

C₂H₄ (g) + 3 O₂ (g) ------------------------ 4 CO₂ (g) + 2 H₂O (l) ΔH⁸ = ?

ΔH⁸f kJmol 52.47 0 -399.5 -285.83

ΔH⁸ = 2(-399.5) + 2 (-285.83) - (52.47)

ΔH⁸ = -1420 kJ/mol

b.

H₂S (g) + 3 O₂ (g) ---------------------- 2 H₂O (l) + 2 SO₂ (g)

ΔH⁸f kJmol -20.50 0 -285.83 -296.84

ΔH⁸ = 2(-285.83) + 2 (-296.84) - (-20.50)

ΔH⁸ = -1144.84 kJ/mol

4 0

3 years ago

Briefly explain two chemical tests which can be used to identify the formation of this compound as aldehyde or ketone.

Sveta_85 [38]

Answer:

The correct answer is :

1) Fehling's test,

2) Tollen's test

Explanation:

1. Fehling's Test is the test that confirms the presence of aldehydes by the Fehling solution that contain copper ion with tartrate ions in NaOH solution. The color of the solution is blue due to presence of copper ions. In this test aldehydes are confirmed by the reduction of the blue solution to a insoluble precipitate of copper oxide red color while in presence of ketones there is no change.

2. Tollen's test is also a test that help in identifying the presence of aldehyde as the Tollen's reagents oxidizes aldehydes where ketones as they lack hydrogen in them.

Thus, the correct answer is : 1) Fehling's test,

2) Tollen's test.

7 0

3 years ago