28.5 g of iron is added to a graduated cylinder containing 45.5 mL of water. The water level rises to 49.1 mL. The density of the iron is

7.92 g/mL.

Explanation:

The following data were obtained from the question:

Mass of Iron = 28.5 g

Volume of water = 45.5 mL

Volume of water + Iron = 49.1 mL.

Density of Iron =.?

Next, we shall determine the volume of the iron. This can be obtained as illustrated below:

Volume of water = 45.5 mL

Volume of water + Iron = 49.1 mL.

Volume of iron =.?

Volume of iron = (Volume of water + Iron) – (volume of water)

Volume of iron = 49.1 – 45.5

Volume of iron = 3.6 mL

Finally, we shall determine the density of iron as follow:

Mass of Iron = 28.5 g

Volume of iron = 3.6 mL

Density of Iron =.?

Density = mass/volume

Density = 28.5/3.6

Density = 7.92 g/mL

Therefore, the density of the iron is 7.92 g/mL

with this one i know the answer in craters one reason i looked it up and i learned about it there is my evidence

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2