All categories

3 years ago

13. A new mystery novel will cost Ally $26.60. If she earns $6.65 an hour, how many hours will

Chemistry

2 answers:

ehidna [41]3 years ago

6 0

Answer:

the answer is c

Explanation:

because if she earns 6.65 an our and the novel will cots 26.60 i just divided 26.60%6.65 and i got 4

Charra [1.4K]3 years ago

3 0

Answer : C

Because $6.65 multiplied by 4 hours equals $26.60

You might be interested in

The dissociation of sulfurous acid (H2SO3) in aqueous solution occurs as follows:

aksik [14]

Answer:

The [SO₃²⁻]

Explanation:

From the first dissociation of sulfurous acid we have:

H₂SO₃(aq) ⇄ H⁺(aq) + HSO₃⁻(aq)

At equilibrium: 0.50M - x x x

The equilibrium constant (Ka₁) is:

$K_{a1} = \frac{[H^{+}] [HSO_{3}^{-}]}{[H_{2}SO_{3}]} = \frac{x\cdot x}{0.5 - x} = \frac {x^{2}}{0.5 -x}$

With Ka₁= 1.5x10⁻² and solving the quadratic equation, we get the following HSO₃⁻ and H⁺ concentrations:

$[HSO_{3}^{-}] = [H^{+}] = 7.94 \cdot 10^{-2}M$

Similarly, from the second dissociation of sulfurous acid we have:

HSO₃⁻(aq) ⇄ H⁺(aq) + SO₃²⁻(aq)

At equilibrium: 7.94x10⁻²M - x x x

The equilibrium constant (Ka₂) is:

$K_{a2} = \frac{[H^{+}] [SO_{3}^{2-}]}{[HSO_{3}^{-}]} = \frac{x^{2}}{7.94 \cdot 10^{-2} - x}$

Using Ka₂= 6.3x10⁻⁸ and solving the quadratic equation, we get the following SO₃⁻ and H⁺ concentrations:

$[SO_{3}^{2-}] = [H^{+}] = 7.07 \cdot 10^{-5}M$

Therefore, the final concentrations are:

[H₂SO₃] = 0.5M - 7.94x10⁻²M = 0.42M

[HSO₃⁻] = 7.94x10⁻²M - 7.07x10⁻⁵M = 7.93x10⁻²M

[SO₃²⁻] = 7.07x10⁻⁵M

[H⁺] = 7.94x10⁻²M + 7.07x10⁻⁵M = 7.95x10⁻²M

So, the lowest concentration at equilibrium is [SO₃²⁻] = 7.07x10⁻⁵M.

I hope it helps you!

8 0

3 years ago

Give the name for the strongest intermolecular interaction between the substrate and the following amino acids on the star prote

mel-nik [20]

Answer:

The answer is IONIC BOND

Explanation:

Steroidogenic acute regulatory, (StAR) protein is a type of globular protein, which allows it act as an active catalyst on substrates. Because the substrates on which enzymes act usually have higher molecular weights of several hundred as compared to the enzymes, only a fraction of the enzyme's surface is in contact with the substrate. This region of contact called the active site, is as a result of the protein folding itself into a tertiary structure.

Once the correct substrate has bound at the active site of the enzyme, an enzyme-substrate complex is created. The substrate is usually held in the complex by combinations of electrical attraction, hydrophobic repulsion, or hydrogen bonding between and from the amino acid; the strongest of which is the ionic/electrostatic bonding due to larger amount of ionic "R" groups in the protein structure.

So whilst all these inter-molecular interactions are possible, the strongest would be ionic bond.

4 0

3 years ago

CHEMISTRY PLEASE HELP!!!???

Montano1993 [528]

1. Solids

- definite volume & shape

- little energy

-vibrate in place

- very incompressible

2. Liquids

- held together yet can still flow

5 0

3 years ago

Electromagnetic radiation with a wavelength of 525 nm appears as green light to the human eye. The energy of one photon of this

Sedbober [7]

Answer: The energy of one photon of the given light is $3.79\times 10^{-19}J$

Explanation:

To calculate the energy of one photon, we use Planck's equation, which is:

$E=\frac{hc}{\lambda}$

where,

$\lambda$ = wavelength of light = $525nm=5.25\times 10^{-7}m$ (Conversion factor: $1m=10^9nm$ )

h = Planck's constant = $6.625\times 10^{-34}J.s$

c = speed of light = $3\times 10^8m/s$

Putting values in above equation, we get:

$E=\frac{6.625\times 10^{-34}J.s\times 3\times 10^8m/s}{5.25\times 10^{-7}mm}\\\\E=3.79\times 10^{-19}J$

Hence, the energy of one photon of the given light is $3.79\times 10^{-19}J$

3 0

3 years ago

Match the characteristics and elements to their group.

Luba_88 [7]

Answer:

Kr is a Noble Gas. Na is an alkali metal. F is halogen.

Group 17 is halogens. Inert is Noble Gases. Odourless and colourless is Noble Gases. Alkali metals do not occur freely in nature. Alkali metals are malleable

Explanation:

8 0

3 years ago