How many atoms are in 11.5 g of Hg?

A lead–tin alloy of composition 30 wt% Sn–70 wt% Pb is slowly heated from a temperature of 150°C (300°F).(a) At what temperature

Novay_Z [31]

Answer:

a) 231.9 °C

b) 100% Sn

c) 327.5 °C

d) 100% Pb

Explanation:

This is a mixture of two solids with different fusion point:

$Tf_{Pb}=327.5 C$

$Tf_{Sn}=231.9 C$

Given that Sn has a lower fusion temperature it will start to melt first at that temperature.

So the first liquid phase forms at 231.9 °C and because Pb starts melting at a higher temperature, that phase's composition will be 100% Sn.

The mixture will be completely melted when you are a the higher melting temperature of all components (in this case Pb), so it will all in liquid phase at 327.5 °C.

At that temperature all Sn was already in liquid state and, therefore, the last solid's composition will be 100% Pb.

3 0

4 years ago

Will give Brainliest If Correct!

Debora [2.8K]

Answer:

Slowly changing to be slightly more evenly distributed based on humanitarian efforts. Still unevenly distributed leaving millions starving to death.

Explanation:

3 0

3 years ago

Osmium is the most dense element we know of. A 22 g sample of Osmium has a volume of 100 cL. Calculate the density of Osmium in

kakasveta [241]

Answer:

a. V = 1000 mL

b. Denisty = 0.022 g/mL

Explanation:

a.

First we need to convert the volume of the Osmium into mL. For that purpose we are given the conversion unit as:

1 mL = 0.1 cL

Hence, the given volume of Osmium will be:

V = Volume of Osmium = 100 cL = (100 cL)(1 mL/0.1 cL) = 1000 mL

V = 1000 mL

b.

The density of Osmium is given by the following formula:

Density = mass/Volume

Denisty = 22 g/1000 mL

Denisty = 0.022 g/mL

5 0

3 years ago

When ethyl acetoacetate (ch3coch2co2ch2ch3) is treated with one equivalent of ch3mgbr, a gas is evolved from the reaction mixtur

pashok25 [27]

The protons of methylene group between the two carbonyl groups in ethylacetoacetate are acidic in nature. When compounds containing such acidic protons are treated with bases the loose proton and form enolates.

In this particular example when ethylacetoacetate is reacted with methyl magnesium bromide, the methyl group abstracts the acidic proton and converts into methane gas. The enolate when hydrolyzed is again converted into ethylacetoacetate as shown below,

6 0

4 years ago

What is the identity of the element, and how many neutrons does it have? An elements most stable ion forms an ionic compound wit

Pani-rosa [81]

Answer:

B. CA, 14

Explanation:

Atoms of elements contain small particles known as electrons, neutrons, and protons. The nucleus of an atom is made up of neutrons and protons which are at the center of the atom. Electrons on the other hand surrounds the nucleus. Electron has negative charge while proton has a positive charge. The number of neutrons is equivalent to the number of protons . In addition, the number of protons is equal to mass number minus the number of electrons.

For the compound $XCl_{2}$ , it can be broken down into $X^{2+}$ and $2Cl^{-}$ . Its ion has a mass of 34 and 18 electrons which means it has already lost 2 electrons.

Therefore:

For the given element, the number of electrons is 18+2 = 20 electrons.

The number of protons = 34 - 20 = 14.

And the number of neutrons is 14.

Only option B has the correct answer.

6 0

3 years ago