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7. What must you do before you make a hypothesis?

almond37 [142]

Answer:

Ask a question?

Explanation:

look at the scientific method uwu

6 0

3 years ago

015

kozerog [31]

Answer:

Average of measurements = 20.97 cm

Explanation:

Given data:

Three measurements of pete's = 20.9 cm, 21.0 cm, 21.0 cm.

Average value of measurements = ?

Formula:

Average of measurements = sum of all measurements / Total number of measurements

Solution:

Average of measurements = 20.9 cm + 21.0 cm + 21.0 cm. / 3

Average of measurements = 62.9 cm / 3

Average of measurements = 20.97 cm

7 0

3 years ago

The electron configuration of an element is 1s22s22p4. Describe what most likely happens when two atoms of this element move tow

Vlad1618 [11]

Answer:

When the two atoms move towards each other a compound is formed by sharing electron pairs supplied by each of the atoms to enable them have the stable 8 (octet) valency electrons in their outermost shell

Explanation:

The electronic configuration of the given element can be written as follows;

1s²2s²2p⁴

The given electronic configuration is equivalent to that of oxygen, therefore, we have;

The number of electrons in the valence shell = 2 + 4 = 6 electrons

Therefore, each atom requires 2 electrons to complete its 8 (octet) electrons in the outermost shell

When the two atoms move towards each other, they react and combine to form a compound by sharing 4 electrons, 2 from each atom, such that each atom can have an extra 2 electrons in its outermost orbit in the newly formed compound and the stable octet configuration is attained by each of the atoms in the newly formed compound.

4 0

3 years ago

Read 2 more answers

What happens if you put sugar in someone's gas tank?

julsineya [31]

The sugar reacts with the gas, turning it to a semi-solid and sticky substance; clogging the gas lines along with many other things.

4 0

3 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

3 years ago