Help please thank you

, determine the approximate volume of the block.

Jobisdone [24]

I believe the answer is A. 40 mL

8 0

3 years ago

Read 2 more answers

If you have 220 liters O2 at STP how many moles of O2 do you have

Ostrovityanka [42]

Answer: C

Explanation: I GOT IT RIGHT ON MY TEST DUDE AND MY TEACHER SAID IT WAS RIGHT TOO I GOT 100% BRO TRUST ME!

4 0

4 years ago

Solid aluminum and gaseous oxygen react in a combination reaction to produce aluminum oxide: 4Al (s) + 3O2 (g) â†’ 2Al2O3 (s) In

jek_recluse [69]

Answer: The percent yield of the reaction is 74 %

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

$\text{Moles of aluminium}=\frac{2.5g}{27g/mol}=0.092mol$

For oxygen gas:

$\text{Moles of oxygen gas}=\frac{2.5g}{32g/mol}=0.078mol$

The chemical equation for the reaction of titanium and chlorine gas follows:

$4Al(s)+3O_2(g)\rightarrow 2Al_2O_3(s)$

By Stoichiometry of the reaction:

4 moles of aluminium reacts with 3 moles of oxygen.

So, 0.092 moles of aluminium reacts with = $\frac{3}{4}\times 0.092=0.069mol$ of oxygen

As, given amount of oxygen is more than the required amount. So, it is considered as an excess reagent.

Thus, aluminium is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

4 moles of aluminium produce = 2 moles of $Al_2O_3$

So, 0.092 moles of aluminium will produce = $\frac{2}{4}\times 0.092=0.046moles$ of $Al_2O_3$

Now, calculating the mass of aluminium oxide:

$\text{Mass of aluminium oxide}=moles\times {\text {molar mas}}=0.046mol\times 102g/mol=4.7g$

To calculate the percentage yield of titanium (IV) chloride, we use the equation:

$\%\text{ yield}=\frac{\text{Experimental yield}}{\text{Theoretical yield}}\times 100$

Experimental yield = 3.5 g

Theoretical yield = 4.7 g

Putting values in above equation, we get:

$\%\text{ yield of reaction}=\frac{3.5g}{4.7g}\times 100\\\\\% \text{yield of reaction}=74\%$

Hence, the percent yield of the reaction is 74 %

6 0

3 years ago

What volume of 0.25 mol/L solution of lead(II)nitrate would be required to form 500mL of a 0.15 mol/L solution of lead(II)nitrat

mafiozo [28]

To solve this we use the equation,

M1V1 = M2V2

where M1 is the concentration of the stock solution, V1 is the volume of the stock solution, M2 is the concentration of the new solution and V2 is its volume.

0.25 M x V1 = 0.15 M x .500 L

V1 = 0.3 L or 300 mL

5 0

4 years ago

Hello, can someone help me? Please Which velocity changed the most?

saw5 [17]

Answer:

A

Explanation:

Since acceleration is the change of velocity and f=ma, the change in velocity is dependent on force and mass. Since the force on all of the objects is the same, the one with the least mass will accelerate the most. Object A is the least massive at a mass of 0.5kg, meaning that its velocity will change the most. Hope this helps!

3 0

3 years ago