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2 years ago

Why do we use the term formula unit for ionic compounds instead of the term molecule?

1 answer:

3 0

Ionic compounds form crystal lattices, not molecules. The term formula unit is used to indicate the simplest whole-number ratio of ions in the compound.

You might be interested in

Which element on the periodic table is the lowest mass in period 4??

White raven [17]

Answer:

potassium I believe is the correct answer

Explanation:

Potassium is the period four element with the lowest mass; its average mass is 39.0983amu.

8 0

2 years ago

How many electrons does nitrogen need to have a full outer shell

kipiarov [429]

Your answer would be

8

5 0

2 years ago

Consider an exceptionally weak acid, HA, with a Ka = 1x10 -20 . You make a 0.1M solution of the salt Na

Vedmedyk [2.9K]

Answer:

$pH=13$

Explanation:

Hello,

In this case, given the acid, we can suppose a simple dissociation as:

$HA\rightleftharpoons H^+ + A^-$

Which occurs in aqueous phase, therefore, the law of mass action is written by:

$Ka=\frac{[H^+][A^-]}{[HA]}$

That in terms of the change $x$ due to the reaction's extent we can write:

$1x10^{-20}=\frac{x*x}{0.1M-x}$

But we prefer to compute the Kb due to its exceptional weakness:

$Kb=\frac{Kw}{Ka}=\frac{1x10^{-14}}{1x10^{-20}} =1x10^{-6}$

Next, the acid dissociation in the presence of the base we have:

$Kb=\frac{[OH^-][HA]}{[A^-]}=1x10^{6}=\frac{x*x}{0.1-x}$

Whose solution is $x=0.0999M$ which equals the concentration of hydroxyl in the solution, thus we compute the pOH:

$pOH=-log([OH^-])=-log(0.0999)=1$

Finally, since the maximum scale is 14, we can compute the pH by knowing the pOH:

$pH+pOH=14\\\\pH=14-pOH=14-1\\\\pH=13$

Regards.

5 0

3 years ago

Read 2 more answers

Consider the reaction, 2 d(g) + 3 e(g) + f(g) => 2 g(g) + h(g) when h is increasing at 0.64 mol/ls, how quickly is e decreasi

bekas [8.4K]

Answer is: 1,92 mol/L·s.
Chemical reaction: 2D(g) + 3E(g) + F(g) → 2G(g) + H(g).
H is increasing at 0,64 mol/L·s.
From chemical reaction n(H) : n(E) = 1 : 3.
0,64 mol : n(E) = 1 : 3.
n(E) = 1,92 mol.
E is decreasing at 1,92 mol/L·s.

8 0

2 years ago

A fuel was burned for 5 min, increasing the temperature of 10.0 g of water with a density of 1.00 g/ml by 9.0 oC. The fuel relea

jekas [21]

The fuel released 90 calories of heat.

Let suppose that water experiments an entirely sensible heating. Hence, the heat released by the fuel is equal to the heat absorbed by the water because of principle of energy conservation. The heat released by the fuel is expressed by the following formula:

$Q = m\cdot c \cdot \Delta T$ (1)