All categories

3 years ago

I need the 3 questions !!! About Rubidium (Rb) ASAP PLEASE DUE IN LIKE 20 min

Chemistry

1 answer:

hjlf3 years ago

5 0

Answer:

419kJ/mol
5,0,0,+12
That catches fire spontaneously

Explanation:

1. Topic: Chemistry

ElementFirst Ionization Energy (kJ/mol) Lithium520Sodium496Rubidium403Cesium376According to the above table, which is most likely to be the first ionization energy for potassium?

536kJ/mol

504kJ/mol

419kJ/mol

391kJ/mol

358kJ/mol

2. Topic: Chemistry, Atom

The correct set of four quantum numbers for the valence electrons of the rubidium atom (Z=37) is:

5,1,1,+12

5,0,1,+12

5,0,0,+12

5,1,0,+12

3. Rubidium and cesium are pyrophoric. Here the term pyrophoric means:

That hardly catches fire

That does not catch fire at all

That catches fire spontaneously

None of these

You might be interested in

What is the specific heat of a substance if 690 J of heat are required to raise the temperature of a 100 g

tangare [24]

Answer:

Explanation:

8 0

3 years ago

Calculate the pH of a 0.50 M HIO. The Ka of hypoiodic acid, HIO, is 2.3x10–11.0.305.325.479.474.80

never [62]

Answer:

pH = 5.47

Explanation:

The equilibrium that takes place is:

HIO ↔ H⁺ + IO⁻

Ka = $\frac{[H+][IO-]}{[HIO]}$ = 2.3 * 10⁻¹¹

At equilibrium:

[HIO] = 0.5 M - x

[H⁺] = x

[IO⁻] = x

<u>Replacing those values in the equation for Ka and solving for x:</u>

$Ka=\frac{x^2}{0.5-x}=2.3*10^{-11} \\x^2=(2.3*10^{-11})(0.5-x)\\x^2=1.15*10^{-11}-2.3*10^{-11}x\\x^2+2.3*10^{-11}x-1.15*10^{-11}=0\\x=3.39*10^{-6}$

Then [H⁺]=3.39 * 10⁻⁶, thus pH = 5.47

7 0

3 years ago

Consider the following reaction where K. = 154 at 298 K: 2NO(g) + Brz(9) 2NOBr(g) A reaction mixture was found to contain 2.69x1

bekas [8.4K]

Explanation:

$2NO(g) + Br_2(g)\rightleftharpoons 2NOBr(g)$

Equilibrium constant of reaction = $K=154$

Concentration of NO = $[NO]=\frac{2.69\times 10^{-2} mol}{1 L}=2.69\times 10^{-2} M$

Concentration of bromine gas = $[Br_2]=\frac{3.85\times 10^{-2} mol}{1 L}=3.85\times 10^{-2} M$

Concentration of NOBr gas = $[Br_2]=\frac{9.56\times 10^{-2} mol}{1 L}=9.56\times 10^{-2} M$

The reaction quotient is given as:

$Q=\frac{[NOBr]^2}{[NO]^2[Br_2]}=\frac{(9.56\times 10^{-2} M)^2}{(2.69\times 10^{-2} M)^2\times 3.85\times 10^{-2} M}$

$Q=328.06$

$Q>K$

The reaction will go in backward direction in order to achieve an equilibrium state.

1. In order to reach equilibrium NOBr (g) must be produced. False

2. In order to reach equilibrium K must decrease. False

3. In order to reach equilibrium NO must be produced. True

4. Q. is less than K . False

5. The reaction is at equilibrium. No further reaction will occur. False

8 0

2 years ago

Ammonia is an important ingredient in many fertilizers. The main process by which ammonia is made is the Haber process. In this

Basile [38]

"High temperatures make the gas molecules move more quickly" is the one sentence among all the choices given in the question that most likely explains why this reaction is carried out at high temperature. The correct option among all the options that are given in the question is the third option or option "C".

8 0

3 years ago

Read 2 more answers

A CaCl2 solution is given to increase blood levels of calcium. If a patient receives 6.1 mL of a 12 % (m/v) CaCl2 solution, how

Yuliya22 [10]

Mass of CaCl₂ = 0.732 g

<h3>Further explanation</h3>

The concentration of a substance can be expressed in several quantities such as moles, percent (%) weight / volume,), molarity, molality, parts per million (ppm) or mole fraction. The concentration shows the amount of solute in a unit of the amount of solvent.

$\tt \%(m/v)\rightarrow 12\%=\dfrac{mass~CaCl_2}{volume~of~solution}\times 100\%\\\\mass~CaCl_2=12\%\times 6.1\div 100\%\\\\mass~CaCl_2=0.732~g$

5 0

3 years ago