A bottle contains 158.1 grams of lead (II) sulfate (PbSO4), used for car batteries. How many moles does it contain?

1) What happened at Chernobyl in 1986? How many people died?

ch4aika [34]

Answer: According to the BBC, the internationally recognized death toll shows that 31 died as an immediate result of Chernobyl. Two workers died at the site of the explosion, another died in hospital soon after due to their injuries and 28 operators and firemen are believed to have died within three months of the accident.

Explanation:

6 0

2 years ago

How does the tilt of earth affect the climate?

masha68 [24]

The tilt of the earth provides the earth with seasons. As the earth revolved around the sun different portions (northern or Southern Hemisphere) is exposed more directly to the suns radiation, thus it is hotter in those regions. (Why the United States experiences winter in December but Australia experience summer in December.)

3 0

2 years ago

What is the predicted change in the boiling point of water when 1.50 g of

dezoksy [38]

Answer:

0.00735°C

Explanation:

By seeing the question, we can see the elevation in boiling point with addition of BaCl₂ in water

⠀

$\textsf {While} \: \sf {\Delta T_b} \: \textsf{expression is used} \\ \textsf {for elevation of boiling point}$

⠀

The elevation in boiling point is a phenomenon in which there is increase in boiling point in solution, when the particular type of solute is added to pure solvent.

⠀

$\sf \large \underline{The \: formula \: to \: be \: used \: in \: this \: question \: is} \\ \boxed{T_b = i \times K_b \times m}$

⠀

Where 'i' is van't hoff factor which represents the ratio of observed osmotic pressure and the value to be expected.

and 'i' is 3 (as given in the question)

⠀

'Kb' is molal boiling point constant. And it's value is 0.51°C/mol(given in question)

⠀

'm' represent the molality of solution. Molatity is no. of moles of solution present in 1kg of solution.

⠀

To find molality, we have to divide no. of moles of solute by weight of solution

⠀

While first we need to no. of moles

$\sf \implies no. \: of \: moles = \frac{weight \: of \: solute}{molar \: mass \: of \: solute} \\ \\ \implies \sf no. \: of \: moles = \frac{1.5}{208.23} \\ \\ \sf \implies no. \: of \: moles = 0.0072$

⠀

Now, we will find molality

⠀

$\sf \hookrightarrow molality = \frac{no.\: of \: moles}{weight \: of \: solution} \\ \\ \sf \hookrightarrow molality = \frac{0.072}{1.5} \\ \\ \sf \hookrightarrow molality = 0.048 \: mol {kg}^{ - 1}$