1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
stiv31 [10]
3 years ago
12

If the edge length of the unit cell is 705.2 pm, what is the density of KI in g/cm3.

Chemistry
1 answer:
Kipish [7]3 years ago
5 0

The density  is 3.144 g / cm^3.

<u>Explanation</u>:

If effective number of atom in NaCl type structure, z = 4

a = 705.2 pm ⇒ In centimeter = 705.2 \times 10^-10

Na = 6.023 \times 10^23

density = (molecular weight) (z) / (Na) (a^3)

where molecular weight of KI is 166 g,

           Z represents the atomic number

density = (molecular weight) (z) / (Na) (a^3)              

             = (166 \times 4) / (6.023 \times 10^23) \times (705.2 \times 10^-10)

density = 3.144 g / cm^3.

You might be interested in
One method used commercially to peel potatoes is to soak them in a solution of NaOH for a short time and then remove them from t
sergij07 [2.7K]

Answer:

b. 2.28 M

Explanation:

The reaction of neutralization of NaOH with H2SO4 is:

2NaOH + H2SO4 → Na2SO4 + 2H2O

<em>Where 2 moles of NaOH react per mole of H2SO4</em>

<em />

To solve the concentration of NaOH we need to find the moles of H2SO4. Using the chemical equation we can find the moles of NaOH that react and with the volume the molar concentration as follows:

<em>Moles H2SO4:</em>

45.7mL = 0.0457L * (0.500mol/L) = 0.02285 moles H2SO4

<em>Moles NaOH:</em>

0.02285 moles H2SO4 * (2moles NaOH / 1 mol H2SO4) = 0.0457moles NaOH

<em>Molarity NaOH:</em>

0.0457moles NaOH / 0.020L =

2.28M

Right option:

<h3>b. 2.28 M</h3>
7 0
2 years ago
If the energy difference between two electronic states is 214.68 kJ / mol , calculate the frequency of light emitted when an ele
atroni [7]

{\qquad\qquad\huge\underline{{\sf Answer}}}

Here we go ~

Energy difference btween the two electronic states can be expressed as :

{ \qquad \sf  \dashrightarrow \: \Delta E = h\nu}

[ h = planks constant,{\: \nu }= frequency ]

\qquad \sf  \dashrightarrow \:214.68 = 39.79 \times 10 {}^{ - 14}  \times  \nu

\qquad \sf  \dashrightarrow \: \nu =  \cfrac{214.68}{39.79 \times 10 {}^{ - 4} }

\qquad \sf  \dashrightarrow \: \nu =  \cfrac{214.68}{39.79 }  \times 10 {}^{14}

\qquad \sf  \dashrightarrow \: \nu  \approx  5.395 \times10 {}^{14}  \:\:hertz

5 0
1 year ago
There are two physical properties of minerals that both result in smooth, flat surfaces with specific angles between them. The f
stich3 [128]

Answer:

3. crystal habit and cleavage.

Explanation:

Crystal habit is a distinctive characteristic which is shown in its general shape,  crystallographic forms, how developed each form is.

Cleavage is the ability of a mineral to break in smooth planes parallel to zones of weak bonding. Cleavage in three directions at right angles (90o). Cubic cleavage. Cleavage in three directions not at right angles (120o and 60o).

3 0
3 years ago
Why is it better to measure the percent change in mass<br> ratherthan just using the change in mass?
never [62]

Answer: The result is presented in proportion which gives a clearer understanding and accurate result.

Explanation: Percentage change in mass is the proportion of the initial mass of a substance changed after sometime. The results is presented as a percentage making it more accurate and can help to give future reference to weight calculations.

Change is Mass is the mass of a substance left after sometime mostly given in grams. It is not as accurate as percentage change in mass. It is generally better to show results in percentage change in mass as it gives a better understanding of what mass of a substance was lost after a given period or after application of energy like Heat or increased temperature.

6 0
3 years ago
Why is a bowling ball harder to lift than a basket ball? Is it bc a bowling ball is made of metal?
vagabundo [1.1K]
It is more slippery, and it is heavier
5 0
3 years ago
Other questions:
  • A scientist has tested an experimental drug on laboratory mice and created a model. Which of the following is the next logical s
    13·1 answer
  • HELP!!!!! URGENT!!!!!!!!!!!!!!!!!!!!!
    10·1 answer
  • Please help!! Also please provide an explanation
    13·1 answer
  • What is the Empirical Formula when the Molecular Formula is Sb17Br21
    9·1 answer
  • What is the molarity of a solution in which 211g sodium hydrogen carbonate is dissolved in a 10.0L solution?​
    7·1 answer
  • A man uses oars to paddle a boat across a lake, as shown below. The subsequent motion of the boat is best explained by Newton's
    12·2 answers
  • what is the molarity of an HCI solution if 25.0 ml of 0.185 M NaOH is required to neutralize 0.0200 L of HCI?​
    15·1 answer
  • The scientific method is series of six steps used to answer questions or investigate
    9·1 answer
  • Calculate the Gibbs energy, entropy, and enthalpy of mixing when 1.00mol C6H14 (hexane) is mixed with 1.00mol C7H16 (heptane) at
    12·1 answer
  • What pressure (in atm) is required to contain 0.034 moles of oxygen gas in a 5.1 L container at a temperature of 25.00C
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!