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2 years ago

I need help with 17,18,19,& 21

Chemistry

1 answer:

valentinak56 [21]2 years ago

3 0

Answer:

17. tie hair up

wear goggles

18. i don't know

19. you light it on the side of the box

20. it should be orange because that is the safest.

21. you turn down the electricity thing

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Answer:

Explanation:

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1 year ago

The following substances dissolve when added to water. Classify the substances according to the strongest solute-solvent interac

Norma-Jean [14]

Answer:

CuCl2-Ion-dipole forces

CuSO4-Ion-dipole forces

NH3-Dipole-dipole forces

CH3OH-Dipole-dipole forces

Explanation:

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Copper II chloride and copper sulphate are ionic substances hence they dissolve by the mechanism described above.

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3 years ago

The element with 8 electrons in its 3d sublevel is a. O. b. Ne. c. Ar. d. Ni.

Evgesh-ka [11]

The element with 8 electrons in its 3d sublevel is Ni, Nickel. The answer is letter D. The rest of the choices do not answer the question above.

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3 years ago

Read 2 more answers

The rate constant k for a certain reaction is measured at two different temperatures temperature 376.0 °c 4.8 x 108 280.0 °C 2.3

9966 [12]

Answer:

The activation energy for this reaction = 23 kJ/mol.

Explanation:

Using the expression,

$\ln \dfrac{k_{1}}{k_{2}} =-\dfrac{E_{a}}{R} \left (\dfrac{1}{T_1}-\dfrac{1}{T_2} \right )$

Where,

$k_1\ is\ the\ rate\ constant\ at\ T_1$

$k_2\ is\ the\ rate\ constant\ at\ T_2$

$E_a$ is the activation energy

R is Gas constant having value = 8.314×10⁻³ kJ / K mol

$k_2=2.3\times 10^8$

$T_2=280\ ^0C$

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15

So,

T = (280 + 273.15) K = 553.15 K

$T_2=553.15\ K$

$k_1=4.8\times 10^8$

$T_1=376\ ^0C$

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15

So,

T = (376 + 273.15) K = 649.15 K

$T_1=649.15\ K$

So,

$\left(\ln \left(\:\frac{4.8\times \:\:\:10^8}{2.3\times \:\:\:10^8}\right)\right)\:=-\frac{E_a}{8.314\times \:10^{-3}\ kJ/mol.K}\times \:\left(\frac{1}{649.15\ K}-\frac{1}{553.15\ K}\right)$

$E_a=-\frac{10^{-3}\times \:8.314\ln \left(\frac{10^8\times \:4.8}{10^8\times \:2.3}\right)}{-\frac{96}{359077.3225}}\ kJ/mol$

$E_a=-\frac{\frac{8.314\ln \left(\frac{4.8}{2.3}\right)}{1000}}{-\frac{96}{359077.3225}}\ kJ/mol$

$E_a=22.87\ kJ/mol$

The activation energy for this reaction = 23 kJ/mol.

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3 years ago

Describe how two atoms come together to form a single covalent bond.

KATRIN_1 [288]

When an atom donates electrons and other gains electrons, they form ions and the bond is called the ionic bond. When the atoms share electrons between them, they form a molecule, and the bond is called the covalent bond.

The atoms can share one, two or three pairs of electrons in the same bond. If one pair is shared it's called a single bond or a covalent simple; if two pairs are shared it's called a double bond or a covalent double, and if three pairs are shared it's called a triple bond or a covalent triple.

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3 years ago