The biggest polluters of The water in the ground are A home owners b farmers C animals or D plant

Based on the results from this experiment, predict whether some of the following combinations of compounds would precipitate or

iren [92.7K]

Answer:

* No precipitate: $LiOH(aq)+NaCl(aq)\rightarrow LiCl(aq)+NaOH(aq)$

* Precipitate: $3BaCl_2(aq) +2Na_3PO_4(aq) \rightarrow Ba_3(PO_4)_2(s)+6NaCl(aq)$

* Precipitate: $MgSO_4(aq)+2KOH(aq)\rightarrow Mg(OH)_2(s)+K_2SO_4(aq)$

Explanation:

Hello!

In this case, since these all are double displacement reactions, in which the cations and anions are exchanged, we can write the resulting chemical reactions as follows:

a. LiOH and NaCl: No precipitate is formed since LiOH and NaOH are both largely soluble in water:

$LiOH(aq)+NaCl(aq)\rightarrow LiCl(aq)+NaOH(aq)$

b. BaCl2 and Na3PO4: barium phosphate precipitate is formed because it has a large molar mass which makes it insoluble in water:

$3BaCl_2(aq) +2Na_3PO_4(aq) \rightarrow Ba_3(PO_4)_2(s)+6NaCl(aq)$

c. MgSO4 and KOH: magnesium hydroxide "milky" precipitate is formed because it is not soluble in water:

$MgSO_4(aq)+2KOH(aq)\rightarrow Mg(OH)_2(s)+K_2SO_4(aq)$

Moreover, we can relate the solubility of a substance by considering its polarity, molar mass and nature; usually, heavy substances tend to be insoluble in water as well as nonpolar compounds.

Best regards!

6 0

2 years ago

The rate constant of a reaction is measured at different temperatures. A plot of the natural log of the rate constant as a funct

Wittaler [7]

Answer:

The activation energy is 7.11 × 10⁴ J/mol.

Explanation:

Let's consider the Arrhenius equation.

$lnk=lnA-\frac{Ea}{R} .\frac{1}{T}$

where,

k is the rate constant

A is a collision factor

Ea is the activation energy

R is the ideal gas constant

T is the absolute temperature

The plot of ln k vs 1/T is a straight line with lnA as intercept and -Ea/R as slope. Then,

$\frac{-Ea}{R} =-8.55 \times 10^{3} K^{-1} \\Ea= 8.55 \times 10^{3} K^{-1} \times 8.314 \frac{J}{K.mol} =7.11 \times 10^{4} J/mol$

8 0

3 years ago

What is the main gas in our atmosphere?

xxTIMURxx [149]

Answer:

Nitrogen

Explanation:

4 0

3 years ago

Read 2 more answers

Conduction happens as energy flows from a warmer object to a cooler object. Which of the following is evidence of conduction?

Dmitrij [34]

Explanation:

Conduction is a form of heat transfer between one body and another. It usually occurs when a warmer object is in contact with a cooler one. Heat generally flows from a region of high temperature to a place at a lower temperature.

Conduction is very pronounced in solid bodies.
The heat transfer causes a net transfer of the average kinetic energy of one body to the other.
Some examples are: heating of iron by a hotter metallic body, the pot hand getting hotter as cooking continues, cooling of ice by touching it.

8 0

2 years ago

When N2(g) reacts with H2(g) to form NH3(g), 92.2 kJ of energy are evolved for each mole of N2(g) that reacts. Write a balanced

Naddika [18.5K]

Answer:

N₂ + 3H₂ → 2NH₃ ΔH = - 92.2KJ

Explanation:

Let's write out the chemical equation between Nitrogen and Hydrogen to Form Ammonia.

Nitrogen + Hydrogen = Ammonia

N₂ + H₂ → NH₃

A Thermochemical Equation is a balanced stoichiometric chemical equation that includes the enthalpy change, ΔH.

The balanced stoichiometric chemical equation is given as;

N₂ + 3H₂ → 2NH₃

92.2 kJ of energy are evolved for each mole of N2(g) that reacts. And from the equation, 1 mole of N2 reacts.

The enthalpy change, ΔH = - 92.2KJ. The negative sign is because heat is being evolved.

The balanced thermochemical equation;

N₂ + 3H₂ → 2NH₃ ΔH = - 92.2KJ

6 0

3 years ago