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2 years ago

Two reasons why emerging diseases are especially harmful to humans. (is science)

Chemistry

1 answer:

Aleonysh [2.5K]2 years ago

7 0

Answer:

Many emerging diseases arise when infectious agents in animals are passed to humans (referred to as zoonoses). As the human population expands in number and into new geographical regions, the possibility that humans will come into close contact with animal species that are potential hosts of an infectious agent increases.

Explanation:

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Insulin is a protein that is used by the body to regulate both carbohydrate and fat metabolism. A bottle contains 375 mL of insu

Kitty [74]

Mass = Density × Volume
= 30.0 mg / mL × 375 mL
= 11250 mg
= 11.25 g

∴ the total mass of insulin in the bottle is 11.25 g (11250 mg)

4 0

3 years ago

The lone pair of electrons in ammonia allows the molecule to: A.assume a planar structure. B.act as an oxidizing agent. C.act as

serious [3.7K]

Answer:

The correct option is: D.act as a Lewis base in water.

Explanation:

Ammonia is a hydride of nitrogen with the chemical formula NH₃. It is a colorless gas with a characteristic pungent smell. According to the VSEPR theory, it has a trigonal pyramidal structure.

In water, ammonia acts as a Lewis base due to the presence of lone pair on the nitrogen atom. Lewis bases are electron pair or lone pair donors.

8 0

3 years ago

By titration, it is found that 31.7 mL of 0.145 M NaOH(aq) is needed to neutralize 25.0 mL of HCl(aq). Calculate the concentrati

arlik [135]

Answer:

0.184 M

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

HCl + NaOH —> NaCl + H2O

From the balanced equation above, the following data were obtained:

Mole ratio of the acid, HCl (nA) = 1

Mole ratio of the base, NaOH (nB) = 1

Next, the data obtained from the question. This includes:

Volume of the base, NaOH (Vb) = 31.7 mL Molarity of the base, NaOH (Mb) = 0.145 M

Volume of the acid, HCl (Va) = 25.0 mL

Molarity of the acid, HCl (Ma) =?

Finally, we shall determine the molarity of the acid (HCl) as shown below:

MaVa /MbVb = nA/nB

Ma × 25 / 0.145 × 31.7 = 1

Cross multiply

Ma × 25 = 0.145 × 31.7

Ma × 25 = 4.5965

Divide both side by 25

Ma = 4.5965 / 25

Ma = 0.184 M

Therefore, the molarity of the acid (HCl) is 0.184 M

6 0

3 years ago

The formula K₂S indicates that _______.

Pachacha [2.7K]

The subscriot 2 means that in the formula there are two parts of K, and the subscript 1 (implicit) for S, indicates that there is one part of S.

This is, the formula gives the ratio of the elements K and S in the compound, which is:

2 atoms of K : 1 atom of S.

Answer: there are 2 atoms of K and 1 atom of S in a molecule of K2S.

5 0

3 years ago

A sample of gas contains 0.1800 mol of CO(g) and 0.1800 mol of NO(g) and occupies a volume of 23.2 L. The following reaction tak

baherus [9]

Answer:

The volume of the sample is 17.4L

Explanation:

The reaction that occurs requires the same amount of CO and NO. As the moles added of both reactants are the same you don't have any limiting reactant. The only thing we need is the reaction where 4 moles of gases (2mol CO + 2mol NO) produce 3 moles of gases (2mol CO2 + 1mol N2). The moles produced are:

0.1800mol + 0.1800mol reactants =

0.3600mol reactant * (3mol products / 4mol reactants) = 0.2700 moles products.

Using Avogadro's law (States the moles of a gas are directly proportional to its pressure under constant temperature and pressure) we can find the volume of the products:

V1n2 = V2n1

<em>Where V is volume and n moles of 1, initial state and 2, final state of the gas</em>

Replacing:

V1 = 23.2L

n2 = 0.2700 moles

V2 = ??

n1 = 0.3600 moles

23.2L*0.2700mol = V2*0.3600moles

17.4L = V2

<h3>The volume of the sample is 17.4L</h3>

8 0

2 years ago