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4 years ago

14

When designing an experiment, the first step is to. ______. Group of answer choices a. hypothesis b. list a procedure c. state t

he problem d. analyze the data

1 answer:

True [87]4 years ago

8 0

Answer:

A

Explanation:

It's the scientific method

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It is expected that a chemical reaction will occur when copper metal is combined with aqueous zinc sulfate. Explain why there wi

REY [17]

Answer:

$E_{cell}$ = +ve, reaction is spontaneous

$E_{cell}$ = -ve, reaction is non spontaneous

$E_{cell}$ = 0, reaction is in equilibrium

Case 1: when copper metal is combined with aqueous zinc sulfate.

$Cu+ZnSO_4\rightarrow Zn+CuSO_4$

Here copper is undergoing oxidation ad thus acts as anode and zinc is undergoing reduction , thus acts as cathode.

$E^o_{cell}$ = standard electrode potential = $E^0_{cathode}- E^0_{anode}$

Where both $E^0$ are standard reduction potentials.

$E^0_{[Cu^{2+}/Cu]}= +0.34V$

$E^0_{[Zn^{2+}/Zn]}= -0.76V$

$E^0=E^0_{[Zn^{2+}/Zn]}- E^0_{[Cu^{2+}/Cu]}$

$E^0=-0.76-(+0.34)=-1.10V$

Thus as $E_{cell}$ is negative , the reaction is non spontaneous.

Case 2: when zinc metal and aqueous copper sulfate solution are combined.

$Zn+CuSO_4\rightarrow Cu+ZnSO_4$

Here zinc is undergoing oxidation ad thus acts as anode and copper is undergoing reduction , thus acts as cathode.

$E^o_{cell}$ = standard electrode potential = $E^0_{cathode}- E^0_{anode}$

Where both $E^0$ are standard reduction potentials.

$E^0_{[Cu^{2+}/Cu]}= +0.34V$

$E^0_{[Zn^{2+}/Zn]}= -0.76V$

$E^0=E^0_{[Cu^{2+}/Cu]}- E^0_{[Zn^{2+}/Zn]}$

$E^0=+0.34-(-0.76)=+1.10V$

Thus as $E_{cell}$ is positive , the reaction is spontaneous.

3 0

4 years ago

At the center of every atom lies a small, dense ____________ that is positively charged

Sedbober [7]

At the center of every atom lies a small, dense "nucleus" that is positively charged.

Atom is the smallest unit of matter. It is made up of electrons, protons and neutrons. Electrons are negatively charged particles that are found scattered in different energy levels outside the nucleus. Protons are positively charged particles present inside the nucleus. Neutrons do not carry charge and found inside the nucleus. Thus, protons and neutrons make up the nucleus of an atom. Since, protons are positively charged and neutrons are uncharged particles, the charge of nucleus becomes positive.

3 0

3 years ago

Read 2 more answers

Assume that concentrated aqueous NH3 has a density of 0.252 g/mL (0.252 g of NH3 per mL of liquid). Calculate the volume of NH3

Kobotan [32]

The question is incomplete, here is the complete question:

Assume that concentrated aqueous NH₃ has a density of 0.252 g/mL (0.252 g of NH₃ per mL of liquid). Calculate the volume of NH₃ required to contain 0.442 mol?

<u>Answer:</u> The volume of ammonia required is 29.82 mL

<u>Explanation:</u>

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Molar mass of ammonia = 17 g/mol

Moles of ammonia = 0.442 moles

Putting values in above equation, we get:

$0.442mol=\frac{\text{Mass of ammonia}}{17g/mol}\\\\\text{Mass of ammonia}=(0.442mol\times 17g/mol)=7.514g$

To calculate the volume of ammonia, we use the equation:

$\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}$

Density of ammonia = 0.252 g/mL

Mass of ammonia = 7.514 g

Putting values in above equation, we get:

$0.252g/mL=\frac{7.514g}{\text{Volume of ammonia}}\\\\\text{Volume of ammonia}=\frac{7.514g}{0.252g/mL}=29.82mL$

Hence, the volume of ammonia required is 29.82 mL

4 0

3 years ago

Consider the electric field lines for two point charges separated by a small distance. what are the signs of q1 and q2?

Digiron [165]

Assume positive charges

directions outwards from source points like field lines of two repelling magnets

4 0

4 years ago

In terms of d1 and d2, how could you define the bonding atomic radius of atom x?

balu736 [363]

When a covalent bond<span> is present between two </span>atoms<span>, the </span>covalent radius<span> can be determined. When two </span>atoms<span> of the same </span>element<span> are covalently </span>bonded<span>, the </span>radius<span> of each </span>atom<span> will be half the distance between the two nuclei because they equally attract the electrons.</span>

7 0

3 years ago