All categories

3 years ago

I NEED HELP. PLEASE HELP ME!!!!

Chemistry

1 answer:

lidiya [134]3 years ago

5 0

Answer:

We have to add 2RbNO3 (option A)

10 Rb +2RbNO3 → 6 Rb2O + N2

Explanation:

Step 1: The equation:

10 Rb + _____ —> 6 Rb2O + N2

Step 2: Balancing the equation

On the right side we have 6x2 = 12 Rb atoms.

On the left side we have 10x Rb

This means we need to add 2x Rb on the left side.

On the right side we have 2x N, On the left side 0x N.

This means we need to add 2x N on the left side.

On the right side we jave 6x O, on the left side we have 0x O.

This means we need to add 6x O on the left side.

We add this by adding RbNO3

This means we have to add 2x RbNO3 (option A)

10 Rb +2RbNO3 → 6 Rb2O + N2

You might be interested in

5. What happens to the mass when you change<br> the volume?<br> It decreases

anastassius [24]

Explanation:If the mass of the object stays the same but the volume of the object decreases then its density becomes greater. If the volume of the object stays the same but the mass of the object increases then its density becomes greater.

7 0

3 years ago

Aspirin (acetylsalicylic acid, C9H8O4) is a weak monoprotic acid. To determine its acid-dissociation constant, a student dissolv

Triss [41]

Answer:

1. $3.57\times 10^{-4}$ was the $K_a$ value calculated by the student.

2. $5.93\times 10^{-4}$ was the $K_b$ of ethylamine value calculated by the student.

Explanation:

The $pH$ value of Aspirin solution = 2.62

$pH=-\log[H^+]$

$[H^+]=10^{-2.62}=0.00240 M$

Moles of s asprin = $\frac{2.00 g}{180 g/mol}=0.01111 mol$

Volume of the solution = 0.600 L

The initial concentration of Aspirin = c = $\frac{0.01111 mol}{0.600 L}=0.0185 M$

$HAs\rightleftharpoons As^-+H^+$

initially

c 0 0

At equilibrium

(c-x) x x

The expression of dissociation constant :

$K_a=\frac{[As^-][H^+]}{[HAs]}$ :

$K_a=\frac{x\times x }{(c-x)}$

$=\frac{0.00240 M\times 0.00240 M}{(0.0185-0.00240 )}$

$K_a=3.57\times 10^{-4}$

$3.57\times 10^{-4}$ was the $K_a$ value calculated by the student.

The $pH$ value of ethylamine = 11.87

$pH+pOH=14$

$pOH=14-11.87=2.13$

$pOH=-\log[OH^-]$

$[OH^-]=10^{-2.13}=0.00741 M$

The initial concentration of ethylamine = c = 0.100 M

$C_2H_5NH_2+H_2O\rightleftharpoons C_2H_5NH_3^{+}+OH^-$

initially

c 0 0

At equilibrium

(c-x) x x

The expression of dissociation constant :

$K_b=\frac{[C_2H_5NH_3^{+}][OH^-]}{[C_2H_5NH_2]}$ :

$K_b=\frac{x\times x}{(c-x)}$

$=\frac{0.00741\times 0.00741}{(0.100-0.00741)}$

$K_b=5.93\times 10^{-4}$

$5.93\times 10^{-4}$ was the $K_b$ of ethylamine value calculated by the student.

3 0

3 years ago

The force of 20 N acts upon a 5kg block. What is the acceleration of the block?

charle [14.2K]

Answer:

<h2>The answer is 4 m/s²</h2>

Explanation:

The acceleration of an object given it's mass and the force acting on it can be found by using the formula

$a = \frac{f}{m} \\$

where

a is the acceleration

f is the force

m is the mass

From the question

f = 20 N

m = 5 kg

We have

$a = \frac{20}{5} \\$

We have the final answer as

Hope this helps you

8 0

3 years ago

A student drops some metal paper clips in a box of sand. The student uses a magnet to separate the metal paper clips from the sa

Dmitriy789 [7]

Answer:

compound

Explanation:

because now there are one together

3 0

3 years ago

Arrange the sublevels in ascending order by the number of electrons they can contain. p sublevel s sublevel d sublevel f subleve

inn [45]

Electronic configuration of the atom describes the arrangemnet of electrons in different shells and subshells ( sublevels).

Now , there are 4 types of sublevels: s, p , d and f . These sublevels have orbital which are spaces with high probability of having an electron and each orbital can have maximum 2 electrons.

Therefore,

s-sublevel has 1 orbital - it can have maximum 2 electrons.

p-sublevel has 3 orbitals - it can have maximum 6 electrons

d-sublevel has 5 orbitals - it can have maximum 10 electrons

f-sublevel has 7 orbitals - it can have maximum 14 electrons.

Hence, the acsending order of sublevels in terms of maximum number of electrons is:

3 0

3 years ago

Read 2 more answers