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2 years ago

If there is a New Moon at midnight on October 1, when would the next New Moon occur?

1 answer:

8 0

Answer: C

Explanation: A lunar month is 29.53 earth days. Since an earth calendar as only integer days, it could be either 29 or 30 days later.

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Sugar when dissolved into water, propose whether the compound forms atoms, molecules or lattices. Justify you answer

kirza4 [7]

Answer:

atoms

Explanation:

for sugar to dissolve in water hydaration must be equal to or greater than the lattice energy or molecular forces so when the molecular forces breaks new atoms are formed for recombination in new compound

6 0

2 years ago

The solubility product of PbI2 is 7.9x10^-9. What is the molar solubility of PbI2 in distilled water?

Agata [3.3K]

<u>Answer:</u> The molar solubility of $PbI_2$ is $1.25\times 10^{-3}mol/L$

<u>Explanation:</u>

Solubility is defined as the maximum amount of solute that can be dissolved in a solvent at equilibrium.

Solubility product is defined as the product of concentration of ions present in a solution each raised to the power its stoichiometric ratio.

The balanced equilibrium reaction for the ionization of calcium fluoride follows:

$PbI_2\rightleftharpoons Pb^{2+}+2I^-$

s 2s

The expression for solubility constant for this reaction will be:

$K_{sp}=[Pb^{2+}][I^-]^2$

We are given:

$K_{sp}=7.9\times 10^{-9}$

Putting values in above equation, we get:

$7.9\times 10^{-9}=(s)\times (2s)^2\\\\7.9\times 10^{-9}=4s^3\\\\s=1.25\times 10^{-3}mol/L$

Hence, the molar solubility of $PbI_2$ is $1.25\times 10^{-3}mol/L$

3 0

2 years ago

When water freezes into ice, sme of the properties have changed <br> What stays the same

larisa86 [58]

When water freezes into ice, some of the properties have change. What stays the same.

Answer: 1: Ice Melting is a physical change. When liquid water (H2O) freezes into a solid state (ice), it appears changed; However, this change is only physical as the the composition of the constituent molecules is the same: 11.19% hydrogen and 88.81% oxygen by mass.

Have a goood day!

5 0

2 years ago

Can you please help me (50 points)

Anna35 [415]

Answer:

P=15

N=59

Explanation:

Pic is blurry but I based my answer on bottom number being 74

4 0

1 year ago

How many molecules of propane were in the erlenmeyer flask? Avogadro's number is 6. 022 × 10^23 molecules/mol

Ede4ka [16]

3.74× $10^{21}$

3.74 × $10^{21}$ molecules of propane were in the erlenmeyer flask.

number of moles of propane can be calculated as moles of propane.

mass of propane = 0.274 g

molar mass of propane = 44.1

So this gives us the value of 6.21× $10^{-3}$ moles of propane

No one mole of propane As a 6.0-2 × $10^{23}$

so, 6.21 × $10^{-3}$ × 6. 022 × 10^23

= 3.74 × $10^{21}$

Therefore, molecules of propane were in the erlenmeyer flask is found to be 3.74 × $10^{21}$

<h3>What is erlenmeyer flask?</h3>

A laboratory flask with a flat bottom, a conical body, and a cylindrical neck is known as an Erlenmeyer flask, sometimes known as a conical flask or a titration flask.
It bears the name Emil Erlenmeyer after the German chemist.

<h3>What purpose does an Erlenmeyer flask serve?</h3>

Liquids are contained in Erlenmeyer flasks, which are also used for mixing, heating, chilling, incubating, filtering, storing, and other liquid-handling procedures.

For titrations and boiling liquids, their sloped sides and small necks make it possible to whirl the contents without worrying about spills.

To learn more about calculating total molecules visit:

brainly.com/question/8933381

#SPJ4

4 0

11 months ago