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2 years ago

6.

1 answer:

6 0

Answer: THE ANSWER IS OZONE WEEEE a layer in the earth's stratosphere at an altitude of about 6.2 miles (10 km) containing a high concentration of ozone, which absorbs most of the ultraviolet radiation reaching the earth from the sun.

Explanation:

You might be interested in

What are other portals of entry besides needlesticks?

aivan3 [116]

Answer:

Inhalation (via the respiratory tract)Absorption (via mucous membranes such as the eyes) Ingestion (via the gastrointestinal tract)

Explanation:

The opening where an infectious disease enters the host's body such as mucus membranes, open wounds, or tubes inserted in body cavities like urinary catheters or feeding tubes.

6 0

1 year ago

Gifblaar is a small South African shrub and one of the most poisonous plants known because it contains fluoroacetic acid (FCH2CO

PSYCHO15rus [73]

[H_{3}O^{+}] = 0.00770 M

The equilibrium equation representing the dissociation of $FCH_{2}COOH$

$FCH_{2}COOH(aq) + H_{2}O (l) FCH_{2}COO^{-}(aq)+ H_{3}O^{+}(aq)$

Given [H_{3}O^{+}] = 0.00770 M

Let the initial concentration of acid be x and change y

So y = $[H_{3}O^{+}]$ = $[FCH_{2}COO^{-}]$ = 0.00770 M

$pK_{a} = 2.59K_{a} = 10^{-2.59} = 0.00257 M$

$K_{a} = \frac{(0.00770 M)(0.00770 M)}{x - 0.00770}$

$0.00257 = \frac{0.00005929}{x - 0.00770}$

0.00257 x - 0.00001979 = 0.00005929

x = 0.031 M

Therefore, initial concentration of the weak acid is 0.031 M

4 0

3 years ago

Which type of bond is found between atoms of solid cobalt?

Vsevolod [243]

The answer is (3) metallic. Cobalt is a transition metal, so it can't be covalent bonds, which bond non-metals, therefore eliminating choice 1 and 2. Ionic bonds are between metals and non metals, but solid cobalt does not have a non metal, eliminating choice 4 as well. Metallic bonds are bonds between metals, therefore the answer is (3) metallic.

3 0

3 years ago

Read 2 more answers

1. A cupcake show makes and delivers specialized cupcakes. It will cost someone $30 for

lorasvet [3.4K]

Answer:

2.5

Explanation:

The given costs for the purchase and delivery of the cupcakes are;

The cost of 10 cupcakes and the delivery fee = $30

The cost of 25 cupcakes and the delivery fee = $67.50

Let 'c' represent the fixed cost of delivery of the cup cakes, and let 'x' represent the cost of each cup cake, we have;

30 = 10·x + c...(1)

67.50 = 25·x + c...(2)

Subtracting equation (1) from equation (2) gives;

67.50 - 30 = 37.50 = 25·x - 10·x + c - c = 15·x

∴ x = 37.50/15 = 2.5

The cost of each cupcake, x = 2.5

(∴ The delivery fee = 30 - 10 × 2.5 = 5)

The cost of each cupcake is 2.5.

8 0

2 years ago

Which of the following statements explain why the van der Waals equation must be used to describe real gases? X. interactions be

8090 [49]

Answer:

Statements Y and Z.

Explanation:

The Van der Waals equation is the next one:

$nRT = (P + \frac{an^{2}}{V^{2}})(V -nb)$ (1)

The ideal gas law is the following:

$nRT = PV$ (2)

where n: is the moles of the gas, R: is the gas constant, T: is the temperature, P: is the measured pressure, V: is the volume of the container, and a and b: are measured constants for a specific gas.

As we can see from equation (1), the Van der Waals equation introduces two terms that correct the P and the V of the ideal gas equation (2), by the incorporation of the intermolecular interaction between the gases and the gases volume. The term an²/V² corrects the P of the ideal gas equation since the measured pressure is decreased by the attraction forces between the gases. The term nb corrects the V of the ideal gas equation, taking into account the volume occuppied by the gas in the total volume, which implies a reduction of the total space available for the gas molecules.

So, the correct statements are the Y and Z: the non-zero volumes of the gas particles effectively decrease the amount of "empty space" between them and the molecular attractions between gas particles decrease the pressure exerted by the gas.

Have a nice day!

5 0

3 years ago