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3 years ago

Which of the following statements statements expresses the following chemical equation with words?

1 answer:

7 0

Answer:What are the two half reactions that show how many electrons are gained or lost by each species in the reaction:

Ni2+(aq) + Mg(s) → Ni(s) + Mg2+(aq)?

atoms cannot be created or destroyed in a chemical reaction

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In your double replacement reaction, the more reactive metal "pushed" the other one out of its place. Without using the Internet

irakobra [83]

You are using the internet right now. The question told you not to. Lol

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3 years ago

In old times, before there were train signals, people who worked on the railroad would often put their ear down to the train tra

anzhelika [568]

Sound waves travel faster in denser materials and the more dense the material the faster the sound is

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3 years ago

Calculate the amount of heat needed to boil 120.g of acetic acid (HCH3CO2), beginning from a temperature of 16.7°C.

evablogger [386]

Answer:

The total amount of heat needed = 72.2116 kJ

Explanation:

Given that ;

the mass of acetic acid = 120.0 g

The initial temperature $T_1$ = 16.7 °C = (16.7 + 273.15 ) K = 298.85 K

The standard molar mass of acetic acid = 60.052 g/mol

Thus ; we can determine the number of moles of acetic acid;

number of moles of acetic acid = mass of acetic acid/ molar mass of acetic acid

number of moles of acetic acid = 120.0 g/ 60.052 g/mol

number of moles of acetic acid = 1.998 moles

For acetic acid:

The standard boiling point $T_2$ = 118.1 °C = ( 118.1 + 273.15 ) K = 391.25 K

The enthalpy of vaporization of acetic acid $\Delta H_{vap}$ = 23.7 kJ/mol

The heat capacity of acetic acid c = 2.043 J/g.K

The change in temperature Δ T = $T_2 - T_1$

Δ T = (391.25 - 289.85)K

Δ T = 101.4 K

The amount of heat needed to bring the liquid acetic acid at 16.7°C to its boiling point is ;

q = mcΔT

From our values above;

q = 120 g × 2.043 J/g.K × 101.4 K

q = 24859.2 J

q = 24859 /1000 kJ

q = 24.859 kJ

we have earlier calculated our number of moles o f acetic acid to be 1.998 moles;

Thus;

The needed amount of heat = $\Delta_{vap} *numbers \ of \ moles$

The needed amount of heat = $23.7 \ kJ/mol * 1.998 \ moles$

The needed amount of heat = 47.3526 kJ

Hence;

The total amount of heat needed = 24.859 kJ + 47.3526 kJ

The total amount of heat needed = 72.2116 kJ

4 0

3 years ago

Lattice energy is ____.

Citrus2011 [14]

Answer:

(B) the energy required to break apart one mole of an ionic compound into its gaseous ions

Explanation:

Lattice energy is the energy that would be obtained from the formation of an ionic compound from its gaseous ions. Therefore, the reverse process that responds the question would be the energy required to break apart an ionic compound and convert its component atoms into gaseous ions.

Lattice energy provides a measure of the stability of an ionic compound. When the ions bind to form the crystalline structure, heat (energy) is released. To break the ionic compound into the ions that form it, it is necessary to provide an energy equal to that released when formed, i.e. the lattice energy.

3 0

4 years ago

If 30cm³ of 0.45 mol dm3 HCl reacted with NaOH, how many moles of HCl reacted?

77julia77 [94]

Moles HCl reacted : 0.0135

<h3>Further explanation</h3>

Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution

$\large {\boxed {\bold {M ~ = ~ \dfrac {n} {V}}}$

Where

M = Molarity

n = Number of moles of solute

V = Volume of solution

So to find the number of moles can be expressed as

n = V x M

The volume of HCl 30 cm³=3.10⁻² dm³

Molarity of HCl = 0.45 mol/dm³

so moles HCl reacted :

$\tt n=3.10^{-2}\times 0.45=0.0135$

3 0

3 years ago