Which choice is an element? carbon dioxide water carbon air

How many milliliters of sterile water for injection should be added to a vial containing 5 mg/mL of a drug to prepare a solution

jonny [76]

Answer:

7mL of sterile water is the initial amount of the concentrated solution is 3mL

Explanation:

In this problem, the vial must be <em>diluted </em>from 5mg/mL to 1.5mg/mL, that means the solution must be diluted:

5mg/mL / 1.5mg/mL = 3.33 times

If the initial amount of the drug in the vial is 3mL, the final volume must be:

10mL

That means the volume of water that should be added is:

10mL - 3mL:

<h3>7mL of sterile water is the initial amount of the concentrated solution is 3mL</h3>

4 0

3 years ago

If the reactants are 10 kg what is the mass of the products

nlexa [21]

If the mass of both the reactants is 10kg then the mass of the products also equals 10kg.

It is due to the law of conservation of mass.

Mass can neither be created nor be destroyed.

7 0

3 years ago

The concentration in molality of hcl in a solution that is prepared by dissolving 5.5 g of hcl in 200.0 g of c2h6o is __________

PIT_PIT [208]

Molality is one way of expressing concentration of a solute in a solution. It is expressed as the mole of solute per kilogram of the solvent. To calculate for the molality of the given solution, we need to convert the mass of solute into moles and divide it to the mass of the solvent.

<span>
Moles of HCl = 5.5 g HCl ( 1 mol HCl / 36.46 g HCl ) = 0.1509 mol HCl</span>

<span>
Molality = 0.1509 mol HCl / 200 g C2H6O ( 1 kg / 1000 g )
Molality = 0.7543 mol / kg</span>

<span>The concentration in molality of hcl in a solution that is prepared by dissolving 5.5 g of hcl in 200.0 g of c2h6o is 0.7453 molal.</span>

6 0

3 years ago

A cat travels 240 meters in 30 seconds, and a sprinter travels 100 meters in 9.5 seconds. Which is traveling faster, the cat or

joja [24]

Answer:

The cat

Explanation:

1) You need to find how many meters per second each thing is sprinting, so you can divide the meters by seconds for each.

$\frac{240}{30} = 8 m/s\\\frac{100}{9.5} = around 10.5 m/s$

2) Per second, the sprinter is able to achieve 8 meters, while the cat can do around 10.5 meters. 10.5 is greater than 8, making the cat faster than the sprinter.

4 0

2 years ago

What is the final, balanced equation that is formed by combining these two half reactions?

lara31 [8.8K]

Answer: Balanced equation that is formed by combining these two half reactions is $Cu + NO^{-}_{3} + 2H^{+} \rightarrow Cu^{2+} + NO^{-}_{2} + H_{2}O$ .

Explanation:

A chemical equation which contains same number of atoms on both reactant and product side is called a balanced chemical equation.

For example, $Cu \rightarrow Cu^{2+} + 2e^{-}$

$NO^{-}_{3} + 2e^{-} + 2H^{+} \rightarrow NO^{-}_{2} + H_{2}O$

On cancelling the common species from both these half-reactions, the complete balanced equation will be as follows.

$Cu + NO^{-}_{3} + 2H^{+} \rightarrow Cu^{2+} + NO^{-}_{2} + H_{2}O$

Thus, we can conclude that balanced equation that is formed by combining these two half reactions is $Cu + NO^{-}_{3} + 2H^{+} \rightarrow Cu^{2+} + NO^{-}_{2} + H_{2}O$ .

7 0

3 years ago