All categories

3 years ago

Construction crews sometimes use this reaction for welding underwater structures:

Chemistry

1 answer:

meriva3 years ago

5 0

Answer:

5 moles of iron formed

Explanation:

Given data:

Moles of iron formed = ?

Moles of iron oxide react = 2.50 mol

Solution:

Chemical equation:

Fe₂O₃ + 2Al → Al₂O₃ + 2Fe

Now we will compare the moles of iron with iron oxide.

Fe₂O₃ : Fe

1 ; 2

2.50 : 2×2.50 = 5 mol

You might be interested in

Neon is compressed from 100 kPa and 16°C to 500 kPa in an isothermal compressor. Determine the change in the specific volume and

Viktor [21]

Answer:

$\Delta v=-0.952m^3/kg$

$\Delta h=0$

Explanation:

In this case, since neon could be considered as an ideal gas, the specific volumes at the first and second state are respectively:

$v_1=\frac{Rg*T_1}{p_1}=\frac{0.4119kJ/kg*K*289.15}{100kPa} =1.19m^3/kg\\$

$v_2=\frac{Rg*T_2}{p_2}=\frac{0.4119kJ/kg*K*289.15}{500kPa} =0.238m^3/kg\\$

Thus, the change in the specific volume turns out:

$\Delta v=v_2-v_1=0.238m^3/kg-1.19m^3/kg\\\Delta v=-0.952m^3/kg$

Which value has sense for the compression.

In addition, the specific enthalpy change just depend on the temperature as it is an ideal gas, therefore, since the process es isothermic:

$\Delta h=Cp\Delta T=0$

Best regards.

3 0

4 years ago

A solution is made by dissolving 100. g of cobalt(III)chloride in 250. g of water. to make a solution that has a density of 1.25

Mariulka [41]

Answer:

Option A) (I) 2.42 m (II) 2.16 M

Explanation:

Let's determine some information.

Solute = CoCl₃ (molar mass = 165.29 g/m); mass of 100 g

Solvent = Water, mass of 250 g

Solution mass = mass of CoCl₃ + mass of water

250 g + 100 g = 350 g of solution

If we want to reach molarity (mol/L), let's determine solution volume with density:

Solution density = solution mass / solution volume

1.25 g/mL = 350 g / solution volume

Solution volume = 350 g / 1.25 g/mL = 280 mL

Let's convert the volume to L → 280 mL = 0.280L

Let's convert the mass of solute to moles = 100 g / 165.29 g/m →0.605 mol

Mol/L = 0.605 moles / 0.280 L = 2.16 M

Now let's calculate molalilty (mol/kg of solvet)

We must convert solvent mass to kg → 250g = 0.250 kg

Then, 0.605 moles / 0.250 kg =2.42 m

8 0

4 years ago

Ionic bonds are ___________ than covalent bonds and are ___________ common in cells.

sammy [17]

Answer:

Ionic bonds are stronger than covalent bonds

8 0

2 years ago

In a chemical equation, the symbol that takes the place of the word yields is an) Example: HCI + KOH-KCI + H2O

Masteriza [31]

Answer:

Arrow.

Explanation:

Hello!

In this case, since chemical reactions are characterized by the presence of some species at the left on an arrow representing the reactants and at the right the products, we understand that the arrow, separating reactants and products is understood as "produces" or in very chemical words "yields"; therefore, the symbol that takes the place of the word yields is an arrow.

Best regards!

4 0

3 years ago

Thermal energy is apart of what state of matter?

Rashid [163]

Answer:

solid

Explanation:

When a solid is melted, for example, thermal energy is what causes the bonds within the solid to break apart.

5 0

4 years ago