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3 years ago

Explain why a magnesium atom is smaller than atoms of both sodium and calcium.

1 answer:

5 0

In the periodic table, there is a size trend.
The trend occurs horizontally and vertically on the table.
- From right to left, the atomic radius gets larger.
- From top to bottom, the atomic radius gets larger.

The reasoning for this is the additional energy levels and electrons being added as you go from right to left or top to bottom.
We can see that Magnesium is higher and more right in the periodic table than sodium and calcium.
Thus, Magnesium has a smaller atomic radius than both sodium and calcium

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Does anyone have any idea what this means lol

miv72 [106K]

Answer:

29.42 Litres

Explanation:

The general/ideal gas equation is used to solve this question as follows:

PV = nRT

Where;

P = pressure (atm)

V = volume (L)

n = number of moles (mol)

R = gas law constant (0.0821 Latm/molK)

T = temperature (K

According to the information provided in this question;

mass of nitrogen gas (N2) = 25g

Pressure = 0.785 atm

Temperature = 315K

Volume = ?

To calculate the number of moles (n) of N2, we use:

mole = mass/molar mass

Molar mass of N2 = 14(2) = 28g/mol

mole = 25/28

mole = 0.893mol

Using PV = nRT

V = nRT/P

V = (0.893 × 0.0821 × 315) ÷ 0.785

V = 23.09 ÷ 0.785

V = 29.42 Litres

6 0

2 years ago

Assume a hydrogen atom has an electron in the n-level corresponding to the month of your birthday (jan = 1, feb = 2, etc.) calcu

luda_lava [24]

My Birthday is in April, So, electron of H atom is in n=4( pfund series).

Ionisation Energy= +13.6(z^2/n^2)
= +13.6(1/16)
= +0.85 eV

6 0

2 years ago

Read 2 more answers

What two things effect the amount of kinetic energy an object has?

marta [7]

Answer:

mass and speed

Explanation:

the motion of an object depends on how fast it's travelling and also how much mass it has

3 0

2 years ago

A compound is found to contain 37.32 % phosphorus , 16.88 % nitrogen , and 45.79 % fluorine by

Alla [95]

Answer: 1. The empirical formula is $PNF_2$

2. The molecular formula is $PNF_2$

Explanation:

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of P = 37.32 g

Mass of N = 16.88 g

Mass of F = 45.79 g

Step 1 : convert given masses into moles.

Moles of P = $\frac{\text{ given mass of P}}{\text{ molar mass of P}}= \frac{37.32g}{31g/mole}=1.20moles$

Moles of N = $\frac{\text{ given mass of N}}{\text{ molar mass of N}}= \frac{16.88g}{14g/mole}=1.20moles$

Moles of F = $\frac{\text{ given mass of F}}{\text{ molar mass of F}}= \frac{45.79g}{19g/mole}=2.41moles$

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For P = $\frac{1.20}{1.20}=1$

For N = $\frac{1.20}{1.20}=1$

For F = $\frac{2.41}{1.20}=2$

The ratio of P: N: F= 1: 1: 2

Hence the empirical formula is $PNF_2$

The empirical weight of $PNF_2$ = 1(31)+1(14)+2(19)= 82.98 g.

The molecular weight = 82.98 g/mole

Now we have to calculate the molecular formula.

$n=\frac{\text{Molecular weight}}{\text{Equivalent weight}}=\frac{82.98}{82.98}=1$

The molecular formula will be= $1\times PNF_2=PNF_2$

3 0

2 years ago

A piston in a heat engine does 500 joules of work, and 1400 joules of heat are added to the system. Determine the change in inte

san4es73 [151]

Answer : The change in internal energy is, 900 Joules.

Solution : Given,

Heat given to the system = +1400 J

Work done by the system = -500 J

Change in internal energy is equal to the sum of heat energy and work done.

Formula used :

$\Delta U=q+w$

where,

$\Delta U$ = change in internal energy

q = heat energy

w = work done

As per question, heat is added to the system that means, q is positive and work done by the system that means, w is negative.

Now put all the given values in the above formula, we get

$\Delta U=(+1400J)+(-500J)=900J$

Therefore, the change in internal energy is 900 J.

The change in internal energy depends on the heat energy and work done. As we will change in the heat energy and work done, then changes will occur in the internal energy. Hence, the energy is conserved.

8 0

2 years ago