Which of the following is not a feature of iron (III) oxide?

At 2°C, the vapor pressure of pure water is 23.76 mmHg and that of a certain seawater sample is 23.09 mmHg. Assuming that seawat

wariber [46]

Answer:

0.808 M

Explanation:

Using Raoult's Law

$\frac{P_s}{Pi}= x_i$

where:

$P_s$ = vapor pressure of sea water( solution) = 23.09 mmHg

$P_i$ = vapor pressure of pure water (solute) = 23.76 mmHg

$x_i$ = mole fraction of water

∴

$\frac{23.09}{23.76}= x_i$

$x_i = 0.9718$

$x_i+x_2=1$

$x_2 = 1- x_i$

$x_2 = 1- 0.9718$

$x_2 = 0.0282$

$x_i = \frac{n_i}{n_i+n_2}$ ------ equation (1)

$x_2 = \frac{n_2}{n_i+n_2}$ ------ equation (2)

where; $(n_2) =$ number of moles of sea water

$(n_i) =$ number of moles of pure water

equating above equation 1 and 2; we have :

$\frac{n_2}{n_i}$ $= \frac{0.0282}{0.9178}$

$= 0.02901$

NOW, Molarity = $\frac{moles of sea water}{mass of pure water }*1000$

$= \frac{0.02901}{18}*1000$

$= 0.001616*1000$

$= 1.616 M$

As we assume that the sea water contains only NaCl, if NaCl dissociates to Na⁺ and Cl⁻; we have $\frac{1.616}{2} =0.808 M$

3 0

3 years ago

Read 2 more answers

For the reaction magnesium plus hyrdogen chloride yeilds hydrogen and magnesium chloride, calculate the percent yield of magnesi

Lina20 [59]

Answer:

Percentage yield of MgCl₂ = 83.4%

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

Mg + 2HCl —> MgCl₂ + H₂

Next we shall determine the mass of of Mg that reacted and the mass of MgCl₂ produced from the balanced equation. This can be obtained as follow:

Molar mass of Mg = 24 g/mol

Mass of Mg from the balanced equation = 1 × 24 = 24 g

Molar mass of MgCl₂ = 24 + (35.5×2)

= 24 + 71

= 95 g/mol

Mass of MgCl₂ from the balanced equation = 1 × 95 = 95 g

SUMMARY:

From the balanced equation above,

24 g of Mg reacted to produce 95 g of MgCl₂.

Next, we shall determine the theoretical yield of MgCl₂. This can be obtained as follow:

From the balanced equation above,

24 g of Mg reacted to produce 95 g of MgCl₂.

Therefore, 100 g of Mg will react to produce = (100 × 95)/24 = 395.83 g of MgCl₂.

Thus, the theoretical yield of MgCl₂ is 395.83 g

Finally, we shall determine the percentage yield of MgCl₂. This can be obtained as follow:

Actual yield of MgCl₂ = 330 g

Theoretical yield of MgCl₂ = 395.83 g

Percentage yield of MgCl₂ =?

Percentage yield = Actual yield /Theoretical yield × 100

Percentage yield = 330 / 395.83 × 100

Percentage yield of MgCl₂ = 83.4%

3 0

3 years ago

7.6 The diagrams show the atoms in four different substances. Each circle represents an atom.

Illusion [34]

Answer:

A and C represent elements while B and D represent Compounds

Explanation:

chemical elements cannot be broken down into simpler substances by any chemical reaction. While A chemical compound is a chemical substance composed of many identical molecules composed of atoms from more than one element held together by chemical bonds

8 0

2 years ago

g The difference between an ionic bond and a covalent bond is that Select one: a. ionic bonds commonly occur between two metals

Bond [772]

Answer:

C) Covalent bonds come about because of a sharing of electrons; ionic bonds do not.

Explanation:

There are two main types of chemical bonds- covalent and ionic/electrovalent bonds.

Ionic bond: Ionic or electrovalent bonds are characterized by the transfer of electrons from electropositive atoms (metals) to electronegative atoms (non-metals). The metal atoms after donating their electrons become positively charged ions (cations) while the non-metal atoms after accepting electrons become negatively charged ions (anions). Strong electrostatic forces of attraction constitutes ionic bonds.

Covalent bond: Covalent bonds are formed by the sharing of electrons by the atoms involved in the bond; usually between atoms of comparable electronegativities or atoms of the same element. The shared electrons are contributed by each of the atoms involved in the bonding or may be contributed by only one of the atoms. In covalent bonding, molecules rather than ions are formed.

8 0

3 years ago

Please help!!!! Thank you

kolezko [41]

The answer is “C“ since the earth rotation makes it seem like the stars and sun is moving when in reality we are moving ฅ^•ﻌ•^ฅ

6 0

3 years ago