First find the moles
moles of the calcium= 72.8 / 40
moles of calcium in 72.8g = 1.82mol
number of atoms= moles x Avogadro constant
atoms = 1.82 x 6.02x10+23
so the number of atoms is 1.096x10+24
Answer:
Molar mass of the gas = 15.15 g/mol
Explanation:
PV = nRT
Where,
P = pressure
n = No. of moles
R = Gas constant
T = Temperature
P = 698 torr, 1 torr = 0.00131579 atm

Temperature = 111 °C = 100 + 273.15 = 384.15 K
V = 48.7 L
R = 0.082057 L atm/mol K
Now, PV = nRT


=1.4189 mol
Molar mass = Mass/ No. of moles
= 21.5/1.4189
=15.15 g/mol
Answer:
<h2>(1). electron electron repulsion</h2><h2>(2). repulsion </h2><h2>(3). attraction </h2><h2>(4). maximum attraction </h2><h2>(5). attractive </h2><h2>(6). repulsive </h2><h2>(7). maximum attraction </h2><h2>(8). molecule </h2>
Explanation:
The same charges repel each other while opposite charges attract each other. During electron-electron interaction repulsion take palace because the electron has negative charges. Nucleus has positive charges so the interaction between two nucleus results in the form of repulsion. When interaction takes place between nucleus and electron then attraction takes place between nucleus and electrons due to opposite charges.
The formation of a bond that takes place due to the sharing of the electrons is known as a covalent bond and thus the covalent molecule is formed.
Answer:
265 mL is the new volume for the gas
Explanation:
We decompose the Ideal Gases Law in order to find the answer of this question: P . V = n . R . T
We can propose the formula for the 2 situations, where n remains constant.
R refers to 0.082 L.atm/mol.K which is physic constant.
We convert the temperature to Absolute value:
67.5°C + 273 = 340.5 K
80°C + 273 = 353 K
We convert the volume to L → 242.2 mL . 1 L/1000 mL = 0.2422 L
We convert the pressure values to atm:
882 Torr . 1 atm/ 760 Torr = 1.16 atm
840 Torr . 1atm / 760 Torr = 1.10 atm
P₁. V₁ / T₁ = P₂ . V₂ / T₂ → Let's replace data:
1.16 atm . 0.2422L / 340.5K = 1.10 atm . V₂ / 353 K
(1.16 atm . 0.2422L / 340.5K) . 353K = 1.10 atm . V₂
V₂ = 0.291 L.atm / 1.10 atm → 0.2647 L ≅ 265 mL
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Hope this helps.