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4 years ago

If an element has 1 valence electrons, how many dots will be in the elements dot diagram?

2 answers:

4 0

The answer is one dot.

The number of dots an element has represented in the diagram, indicates how many valence eletrons( which is the number of electrons in the most exterior energy level of an atom or ion) the element has. So, 1 valence eletron equals one dot.

Stells [14]4 years ago

3 0

There should only be one dot in the elements dot diagram.

You might be interested in

How many moles of Carbon are in 3.06 g of Carbon

natta225 [31]

Answer:

$\boxed {\boxed {\sf 0.255 \ mol \ C }}$

Explanation:

If we want to convert from grams to moles, the molar mass is used. This is the mass of 1 mole. They are found on the Periodic Table as the atomic masses, but the units are grams per mole (g/mol) instead of atomic mass units (amu).

Look up the molar mass of carbon.

Carbon (C): 12.011 g/mol

Set up a ratio using the molar mass.

$\frac {12.011 \ g \ C}{ 1 \ mol \ C}$

Since we are converting 3.06 grams to moles, we multiply by that value.

$3.06 \ g \ C*\frac {12.011 \ g \ C}{ 1 \ mol \ C}$

Flip the ratio. This way, the ratio is still equivalent, but the units of grams of carbon cancel.

$3.06 \ g \ C* \frac{1 \ mol \ C}{12.011 \ g\ C}$

$3.06 * \frac{1 \ mol \ C}{12.011 }$

$\frac {3.06}{12.011 } \ mol \ C$

$0.25476646 \ mol \ C$

The original measurement of grams (3.06) has 3 significant figures, so our answer must have the same. For the number we calculated, that is the thousandth place.

0.25476646

The 7 in the ten-thousandth place tells us to round the 4 up to a 5.

$0.255 \ mol \ C$

3.06 grams of carbon is approximately <u>0.255 moles of carbon.</u>

3 0

2 years ago

PLEASE HELP ASAP!

choli [55]

Answer:

$\large \boxed{\text{D. 710 g}}$

Explanation:

1. Calculate the molar mass of Na₂SO₄

$\begin{array}{ccc}\textbf{Atoms} &\textbf{M}_{\textbf{r}} & \textbf{Mass/u}\\\text{2Na} & 23 & 46\\\text{1S} & 32 & 32\\\text{4O}&16 & 64\\&\text{TOTAL =} & \mathbf{142}\\\end{array}$

The molar mass of Na₂SO₄ is 142 g/mol.

2. Calculate the moles of Na₂SO₄

$\text{Moles of Na$_{2}$SO}_{4} = \text{2.5 L solution} \times \dfrac{\text{2.0 mol Na$_{2}$SO}_{4}}{\text{1 L solution}} = \text{5.0 mol Na$_{2}$SO}_{4}$

3. Calculate the mass of Na₂SO₄

$\text{Mass of Na$_{2}$SO}_{4} = \text{5.0 mol Na$_{2}$SO}_{4} \times \dfrac{\text{142 g Na$_{2}$SO}_{4}}{\text{1 mol Na$_{2}$SO}_{4}} = \text{710 g Na$_{2}$SO}_{4}\\\\\text{You need } \large \boxed{\textbf{710 g}} \text{ of Na$_{2}$SO}_{4}$

6 0

3 years ago

How many grams of Cl are in a 38.0-g sample of the chlorofluorocarbon CF2Cl2

Katena32 [7]

The molecular formula of chlorofluorocarbon is CF₂Cl₂
Molecular mass of CF₂Cl₂ is 120.9 g/mol
Mass of Cl in 1 mol - 2 x 35.5 = 71 g/mol
in 120.9 g of compound - 71 g of Cl
Therefore in 38 g of sample - 71/120.9 x 38 g of Cl
Mass of Cl in 38 g - 22.31 g of Cl

4 0

3 years ago

True or False : An object can be in motion and not in motion at the same time depending on which frame of reference you are comp

marshall27 [118]

Answer:

True

Explanation:

Yes I agree object can be in motion and in not motion at the same time for example there are two men travelling on the bus one person is A another person is B. the person be B rest so by seeing person be the person A also sits but the person see who saw the person be B move along with person C so the the person be B is in rest for person Abut is motion for a person C.

3 0

3 years ago

Describe an experiment to determine the density of a liquid

Tju [1.3M]

Answer:

Take the measuring cylinder and measure its mass, in grams, as accurately as possible. Take the measuring cylinder off the balance and add the water carefully. Put the measuring cylinder back on the balance. Measure and record the new mass . Repeat the procedure, recording the volume and total mass, until the measuring cylinder is full. Then, for each volume calculate the mass of the liquid alone.Repeat steps 1 to 3 Draw a graph of mass of liquid against volume . Calculate the density of each liquid from the gradient of its graph line.

Explanation:

5 0

3 years ago