All categories

3 years ago

When a lab report is cumulative it means that it

1 answer:

4 0

On the cumulative Report, it would be much easier to read for the patients if the ranges in parentheses were tabbed over from the actual result instead of printing directly one space after the result.

You might be interested in

s) Suppose we now collect hydrogen gas, H2(g), over water at 21◦C in a vessel with total pressure of 743 Torr. If the hydrogen g

Elenna [48]

This is an incomplete question, here is a complete question.

Suppose we now collect hydrogen gas, H₂(g), over water at 21°C in a vessel with total pressure of 743 Torr. If the hydrogen gas is produced by the reaction of aluminum with hydrochloric acid:

$2Al(s)+6HCl(aq)\rightarrow 2AlCl_3(aq)+3H_2(g)$

what volume of hydrogen gas will be collected if 1.35 g Al(s) reacts with excess HCl(aq)? Express your answer in liters.

Answer : The volume of hydrogen gas that will be collected is 1.85 L

Explanation :

First we have to calculate the number of moles of aluminium.

Given mass of aluminium = 1.35 g

Molar mass of aluminium = 27 g/mol

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

$\text{Moles of aluminium}=\frac{1.35g}{27g/mol}=0.05mol$

The given chemical reaction is:

$2Al(s)+6HCl(aq)\rightarrow 2AlCl_3(aq)+3H_2(g)$

As, hydrochloric acid is present in excess. So, it is considered as an excess reagent.

Thus, aluminium is a limiting reagent because it limits the formation of products.

By Stoichiometry of the reaction:

2 moles of aluminium produces 3 moles of hydrogen gas

So, 0.005 moles of aluminium will produce = $\frac{3}{2}\times 0.05=0.0750mol$ of hydrogen gas

Now we have to calculate the mass of helium gas by using ideal gas equation.

PV = nRT

where,

P = Pressure of hydrogen gas = 743 Torr

V = Volume of the helium gas = ?

n = number of moles of hydrogen gas = 0.075 mol

R = Gas constant = $62.364\text{ L Torr }mol^{-1}K^{-1}$

T = Temperature of hydrogen gas = $21^oC=[21+273]K=294K$

Now put all the given values in above equation, we get:

$743Torr\times V=0.075mol\times 62.364\text{ L Torr }mol^{-1}K^{-1}\times 294K\\\\V=1.85L$

Hence, the volume of hydrogen gas that will be collected is 1.85 L

8 0

4 years ago

The __________________ of a solution tells how many moles of solute are present per liter.

Stels [109]

Answer:

The MOLARITY of a solution tells how many moles of solute are present per liter

Explanation:

Molarity is a sort of concentration.

It is written as M (mol/L)

5 0

3 years ago

Read 2 more answers

Mixtures can be separated into their components by taking advantage of differences in the chemical properties of the components.

Sedaia [141]

The method of separating mixtures by means of their differences in the chemical properties of the components is less convenient because these methods requires reactions therefore needs energy, increasing the costs for the process.

4 0

3 years ago

Why do alligators need a warm climate?

Reptile [31]

<span>The answer is B.They cannot produce enough heat to keep their bodies warm.

In order to survive, the alligators rely on warm weather, and they are most active when the environment is 82-92 degrees Fahrenheit. They can survive below or above this temperature range but they may spend that time struggling to stay warm or stay cool.

</span>

5 0

3 years ago

A stone is tied to a 0.85-meter cord. it is swung in a circle at a constant rate of 6.0 m/s. what is the centripetal acceleratio

Elan Coil [88]

The correct answer is 42. I know this answer is right because i have already turned my assignment in and got it right.

4 0

3 years ago

Read 2 more answers