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4 years ago

Which of the samples described below contains the FEWEST atoms? No calculation is needed to answer this question.

Chemistry

1 answer:

Monica [59]4 years ago

6 0

Hello!

To do this, use the molar mass. This is how much a mole of an atom weighs. A mole is 6.02214076×10²³ atoms.

Molar masses of:

Se: 78.96 g/mol

Cu: 63.546 g/mol

Ba: 137.327 g/mol

Now, the element with the highest molar mass will have the fewest atoms. This is because the element weighs more, so therefore for the same amount of mass, there will be less of the element needed to reach that mass.

Therefore, 10g of Ba would have the fewest number of atoms.

Hope this helps!

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Type the correct answer in the box. Express your answer to three significant figures. Calcium nitrate reacts with sodium phospha

RoseWind [281]

6.07 grams is the theoretical yield of calcium phosphate (Ca₃(PO₄)₂).

<h3>How we calculate mass from moles?</h3>

Mass of any substance can be calculated by using moles as:

n = W/M, where

W = required mass

M= molar mass

Given chemical reaction is:

3Ca(NO₃)₂ + 2Na₃PO₄ → 6NaNO₃ + Ca₃(PO₄)₂

From the stoichiometry it is clear that:

3 moles of Ca(NO₃)₂ = produce 1 mole of Ca₃(PO₄)₂

Given mass of Ca(NO₃)₂ = 96.1g

Mole of Ca(NO₃)₂ = 96.1g/164g/mol = 0.5859moles

So, 0.5859 moles of Ca(NO₃)₂ = produce 0.5859×1/3 = 0.0196 moles of Ca₃(PO₄)₂

Required mass of Ca₃(PO₄)₂ will be calculated by using moles as:

W = 0.0196mole × 310g/mole = 6.07 grams

Hence, 6.07 grams is the theoretical yield of calcium phosphate.

To know more about moles, visit the below link:

brainly.com/question/15373263

7 0

2 years ago

Which of the following would be considered an Exothermic Reaction?*

Digiron [165]

Answer:

Burning wood

Explanation:

the fire releases heat into the air from the burning wood

6 0

3 years ago

Among the following options, a valid Lewis structure of __________ cannot be drawn without violating the octet rule.

Murrr4er [49]

Answer:

d. IF3

Explanation:

The Octet rule posits that atoms gain, atom lose, or share electrons in order to have a full valence shell of 8 electrons. This statement occurs when atoms also combine to form molecules until they attain or share eight valence electrons either by losing or gaining eletrons.

From the given options, a valid Lewis structure that cannot be drawn without violating the octet rule is IF3

8 0

3 years ago

QUICK HELP PLEASE!!?? Need answer QUICK

d1i1m1o1n [39]

Answer:

Explanation:

Look on the x-axis for the tick marked "60". This indicates 60 degrees Celsius, which we want. Now, look on the y-axis for the tick marked "60". This indicates 60 grams of $Na_2HAsO_4$ . Trace along the graph to find where these two places meet at (60, 60).

Now, look for the solubility curve of $Na_2HAsO_4$ ; it's the yellow-orange line. Find out what the y-coordinate of the point where x = 60 is on the line: it's around (60, 65).

So, since the point (60, 60) is below the line corresponding to this substance, $Na_2HAsO_4$ is unsaturated.

The answer is B.

4 0

4 years ago

Read 2 more answers

Which explains the information needed to calculate speed and velocity?

USPshnik [31]

Answer:

Both require time, but velocity requires displacement and speed requires distance

Explanation:

For calculating speed we require time and distance because speed is defined as the distance per unit time and as speed is a scalar quantity it does not have any direction

But for calculating the velocity we require time as well as displacement because velocity is defined as the displacement per unit time and as velocity is a vector quantity it has direction

Displacement is the shortest distance between the initial position and the final position and it has a specified direction as well

8 0

3 years ago

Read 2 more answers