If 50 milliliters of a 1.0M NaOH solution is

Is a candle melting in the hot sun a chemical or a physical change?

alukav5142 [94]

Chemical, because it is breaking down the chemical and properties in the candle itself.

4 0

3 years ago

How many grams of NH3 are needed to provide the same number of molecules as in 0.85 grams of SF6?

solniwko [45]

Above it says the molecular weights are

NH3- 17g/mol and SF6-146 g/mol

Well 1 mole of SF6 is 146.048 grams (i added hte atomic masses of each element). So then the number of moles in 0.85 grams would be 0.00582000438 moles.

= 1mole / 146.048g * 0.85g

so we would need 0.00582000438 moles of NH3 to have the same number of molecules.

One mole of NH3 is 17.030519999989988 grams (i added each atoms mass). so 0.00582000438 moles of NH3 would be:

= 17.030519999989988 g / mole * 0.00582000438moles

that equals 0.09911770099 grams.

so 0.09911770099 grams is the answer if you round that you get about 0.1 grams

3 0

3 years ago

Read 2 more answers

What is the difference between a liquid and a gas

Bas_tet [7]

Answer:

The molecules of the gas has more kinetic energy and has a lot of space between them. The molecules in the liquid moves slower than gas and has a tighter space than gas. Another difference is liquid takes up the shape of its container while gas does not. Cause its air.

3 0

3 years ago

Blue vitriol is commonly used in industrial dyeing processes. what is the chemical formula for blue vitriol, whose systematic na

fredd [130]

CuSO₄·5H₂O the pentahydrate is the most common form

[Cu(H₂O)₄]SO₄·H₂O → [Cu(H₂O)₄]²⁺ + SO₄²⁻ + H₂O
blue

6 0

3 years ago

Read 2 more answers

What's ligand and how are they classified

KATRIN_1 [288]

Explanation:

Ligands: In co-ordination chemistry ligands are ion, molecule or any species which donates electron pair to central metal atom.

Depending on the type of interaction Ligands are of three types.

Sigma donor only
sigma as well as pi donor
pi acceptor ligand

let's understand each type of Ligands individually & in more detail.

1 - Sigma donor only: This is a unidirectional interaction, in which filled ligand overlaps (head to head) with central metal atom/ion & donates pair of electron in the LUMO of metal.

generally all the molecules of 2nd period without pi bond comes in this category, below are few example of sigma donor ligands,

$\small \sf NH_3, H_2O, CH_3^-, H^-, R-OH, R-NH_3, etc$

2- Pi donor: This in also a unidirectional interaction between ligand & central metal atom but the along with head to head overlap, side overlapping takes place.

generally protonated neutral molecules who have more than one pair to donate show such interaction, for e.g.

NH3 have two lone pair to donate but the energy level of both the lone pairs are different hence when it is neutral it only donates one pair of electron. but when NH3 is protonated to NH2- it have two electron pairs (negative charge+ lone pair) to donate & both the pairs have same energy level. example of such ligands are below,

$\sf \small NH_2^-, OH^-, R-O^-, R-NH^-, F^-, Cl^-, Br^- SH^- etc$

3- Pi acceptor ligand: This is a bidirectional interaction between ligand & central metal atom/ion, the filled orbital of ligand undergoes head to head to overlap with vacant orbital of central metal atom, & filled D orbital of central metal donates their pair to vacant LUMO of ligand.

depending on the LUMO pi acceptor ligands are further classified into two categories.

$d\pi - \sigma* \small \sf When \: lumo \: is \: \sigma*\\ d\pi - \pi* \small \: \sf When \: lumo \: is \: \pi*$

The dπ-σ* is seen in molecules of 3rd period onwards without pi bond for e.g.

PH3, PR3, AsR3 & SR2 etc

The dπ-π* is seen in molecules of 2nd or3rd period with pi bond for e.g.

CO C N- SC N^- etc

Thanks for joining brainly community!

8 0

2 years ago