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3 years ago

What are 3 signs that a chemical reaction is happening, what tells you that this is definitely a chemical reaction?

1 answer:

8 0

Produces heat, putting off air or bubbles and changes the smell or odor it changes the state that’s how you know it is a chemical reaction

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Write balanced net ionic equations for the reactions that occur in each of the following cases. Identify the spectator ion or io

Dmitrij [34]

Answer :

(a) The net ionic equation will be,

$2Cr^{2+}(aq)+3CO_3^{2-}(aq)\rightarrow Cr_2(CO_3)_3(s)$

The spectator ions are, $NH_4^{+}\text{ and }SO_4^{2-}$

(b) The net ionic equation will be,

$Ba^{2+}(aq)+SO_4^{2-}(aq)\rightarrow BaSO_4(s)$

The spectator ions are, $K^{+}\text{ and }NO_3^{-}$

(c) The net ionic equation will be,

$Fe^{2+}(aq)+2OH^{-}(aq)\rightarrow Fe(OH)_2(s)$

The spectator ions are, $K^{+}\text{ and }NO_3^{-}$

Explanation :

In the net ionic equations, we are not include the spectator ions in the equations.

Spectator ions : The ions present on reactant and product side which do not participate in a reactions. The same ions present on both the sides.

(a) The given balanced ionic equation will be,

$Cr_2(SO_4)_3(aq)+3(NH_4)_2CO_3(aq)\rightarrow 3(NH_4)_2SO_4(aq)+Cr_2(CO_3)_3(s)$

The ionic equation in separated aqueous solution will be,

$2Cr^{2+}(aq)+3SO_4^{2-}(aq)+6NH_4^{+}(aq)+3CO_3^{2-}(aq)\rightarrow Cr_2(CO_3)_3(s)+6NH_4^{+}(aq)+3SO_4^{2-}(aq)$

In this equation, $NH_4^{+}\text{ and }SO_4^{2-}$ are the spectator ions.

By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.

The net ionic equation will be,

$2Cr^{2+}(aq)+3CO_3^{2-}(aq)\rightarrow Cr_2(CO_3)_3(s)$

(b) The given balanced ionic equation will be,

$Ba(NO_3)_2(aq)+K_2SO_4(aq)\rightarrow 2KNO_3(aq)+BaSO_4(s)$

The ionic equation in separated aqueous solution will be,

$Ba^{2+}(aq)+2NO_3^{-}(aq)+2K^{+}(aq)+SO_4^{2-}(aq)\rightarrow BaSO_4(s)+2K^{+}(aq)+2NO_3^{-}(aq)$

In this equation, $K^{+}\text{ and }NO_3^{-}$ are the spectator ions.

By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.

The net ionic equation will be,

$Ba^{2+}(aq)+SO_4^{2-}(aq)\rightarrow BaSO_4(s)$

(c) The given balanced ionic equation will be,

$Fe(NO_3)_2(aq)+2KOH(aq)\rightarrow 2KNO_3(aq)+Fe(OH)_2(s)$

The ionic equation in separated aqueous solution will be,

$Fe^{2+}(aq)+2NO_3^{-}(aq)+2K^{+}(aq)+2OH^{-}(aq)\rightarrow Fe(OH)_2(s)+2K^{+}(aq)+2NO_3^{-}(aq)$

In this equation, $K^{+}\text{ and }NO_3^{-}$ are the spectator ions.

By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.

The net ionic equation will be,

$Fe^{2+}(aq)+2OH^{-}(aq)\rightarrow Fe(OH)_2(s)$

3 0

3 years ago

An isotope contains 26 protons, 24 electrons, and 32 neutrons

Anestetic [448]

The correct option is 58 Fe 2+.
A neutral atom normally has the same number of proton, neutron and electrons, if the number of electrons differ from that of proton, that means that the elements has given some electrons away or it has gained some electrons from another element.
In the question given above, the atomic number of the element is 26 [because the proton number is 26], which means the element is iron. Iron has 24 electrons because it has given two away, so it will have +2. The iron has 32 neutrons instead of 26 so it is an isotope.

3 0

3 years ago

Read 2 more answers

Speed of Light Math Quiz (20 points)

Goryan [66]

The wavelength of light : 4.14 x 10⁻⁵ m

<h3>Further explanation </h3>

Radiation energy is absorbed by photons

The energy in one photon can be formulated as

$\large{\boxed{\bold{E\:=\:h\:.\:f}}}$

Where

h = Planck's constant (6,626.10⁻³⁴ Js)

f = Frequency of electromagnetic waves

The energy of the light = 4.8 x 10⁻²¹ J

The wavelength of light :

$\tt E=h.\dfrac{c}{\lambda}\\\\\lambda=\dfrac{h.c}{E}\\\\\lambda=\dfrac{6.626.10^{-34}\times 3.10^8}{4.8.10^{-21}}\\\\\lambda=4.14.10^{-5}~m$

4 0

3 years ago

6. The Earth’s electric field is directed vertically downward; at the ground level its strength is E = 130 N/C, and at an altitu

Alexxx [7]

Answer:

5.31x10⁻⁶ C

Explanation:

The cube is located 100 m altitude from the ground, so the superior face is at 100m and has E = 70 N/C, and the inferior face is at the ground with E = 130 N/C.

The electric field is perpendicular to the bottom and the top of the cube, so the total flux is the flux at the superior face plus the flux at the inferior face:

Фtotal = Ф100m + Фground

Where Ф = E*A*cos(α). α is the angle between the area vector and the field (180° at the topo and 0° at the bottom):

Фtotal = E100*A*cos(180°) + Eground*A*cos(0°)

Фtotal = 70A*(-1) + 130*A*1

Фtotal = 60A

By Gauss' Law, the flux is:

Фtotal = q/ε, where q is the charge, and ε is the permittivity constant in vacuum = 8.854x10⁻¹² C²/N.m²

A = 100mx100m = 10000 m²

q = 60*10000*8.854x10⁻¹²

q = 5.31x10⁻⁶ C

8 0

3 years ago

If Kp = 0.15, which statement is true of the reaction mixture before any reaction occurs?

Fiesta28 [93]

The given sentence is part of a longer question.

I found this question with the same sentence. So, I will help you using this question:

For the reaction N2O4(g) ⇄ 2NO2(g), a reaction mixture at a certain temperature initially contains both N2O4 and NO2 in their standard states (meaning they are gases with a pressure of 1 atm). If Kp = 0.15, which statement is true of the reaction mixture before any reaction occurs?

(a) Q = K; The reaction is at equilibrium.
(b) Q < K; The reaction will proceed to the right.
(c) Q > K; The reaction will proceed to the left.

The answer is the option (c) Q > K; The reaction will proceed to the left, since Qp = 1, and 1 > 0.15.
Explanation:

Kp is the equilibrium constant in term of the partial pressures of the gases.

Q is the reaction quotient. It is a measure of the progress of a chemical reaction.

The reaction quotient has the same form of the equilibrium constant but using the concentrations or partial pressures at any moment.

At equilibrium both Kp and Q are equal. Q = Kp

If Q < Kp then the reaction will go to the right (forward reaction) trying to reach the equilibrium,

If Q > Kp then the reaction will go to the left (reverse reaction) trying to reach the equilibrium.

Here, the state is that both pressures are 1 atm, so Q = (1)^2 / 1 = 1.

Since, Q = 1 and Kp = 0.15, Q > Kp and the reaction will proceed to the left.

6 0

3 years ago