All categories

3 years ago

What describes how to calculate density

Chemistry

1 answer:

Sedaia [141]3 years ago

4 0

Answer:

Explanation:

Which describes how to calculate density?

O mass divided by volume

O volume divided by mass

O mass added to volume

volume subtracted from mass

return

You might be interested in

CalcuLate the velocity of an electron ejected if 300.0 mm of light is applied to the surface. A wavelength of 795 nm has suffici

worty [1.4K]

The equation relating velocity and wavelength is written below:

v = λf
where λ is the wavelength in m while f is frequency in 1/s.

Let's determine first the frequency from the speed of light:
c = distance/time, where c is the speed of light equal to 3×10⁸ m/s
3×10⁸ m/s = (300 mm)(1 m/1000 mm)/ time
time = 1×10⁻⁹ seconds
Since f = 1/t,
f = 1/1×10⁻⁹ seconds = 10⁹ s⁻¹

Thus,
v = (795×10⁻⁹ m)(10⁹ s⁻¹)
v = 795 m/s

8 0

3 years ago

Which of the following is true about the melting temperature of potassium chloride? The melting temperature is relatively high.

allochka39001 [22]

Answer:f

First option: the melting temperature is relatively high.

Explanation:

You can look at the melting temperature at any table that summarizes the main properties of this compound, potassium chloride.

Such melting point is 770 °C, which is relatively high.

Why is this?

Potassium chloride is a ionic compound formed by the cations of potassium, K⁺, and the chloride anions, Cl⁻. Its unit formula is KCl.

The ionic bond between K and Cl is possible because each K atom is able to yield its valence electron to one Cl atom which has 7 valence electrons.

Then, the K atoms become positive ions (cations) K⁺, while Cl atoms become negative ions (Cl⁻).

These two ions with opposite charge are bonded by the force of electrostatic attraction. This is a ionic bond.

Melting point, so as boiling point along with other physical properties, depends on the attraction force between the atoms.

Hence, since the attrative forces between the ions are relatively strong, the melting point of the ionic compounds, such as potassium chloride, are relatively high.

8 0

3 years ago

How many moles of O are present in 2.9 mol of Al2(SO4)3 ?

ad-work [718]

Answer:

34.8 moles of O

Explanation:

First we break down Al2(SO4)3 and look at SO4 only. In this compound, there are already 4 moles of O. Then you see that there are 3 moles of (SO4), meaning there are 3*4 moles of O = 12 moles in the entire compound. Then you look at the question, where it's asking for 2.9 moles of the entire Al2(SO4)3 compound, so you multiply 2.9*12 = 34.8 total moles of O.

6 0

4 years ago

El nombre tradicional CuO

erik [133]

It’s Copper(ll)oxide

5 0

3 years ago

You have 100 grams of potassium fluoride (KF) .

laiz [17]

Answer:

Option C = 1.72 mol

Explanation:

Given data:

Mass of KF = 100 g

Moles of KF = ?

Solution:

First of all we have to calculate the molar mass of KF.

Molar mass of KF = 39.0983 g/mol + 18.998403 g/mol

Molar mass of KF = 58. 0967 g/mol

Formula:

Number of moles = mass/molar mass

Number of moles = 100 g/ 58.0967 g/mol

Number of moles = 1.72 mol

6 0

3 years ago