Answer:
A. When a piece of copper is heated, it combines with oxygen to form copper oxide. The chemical reaction for the same is as follows:
2 Cu (s) + O2(g) => 2CuO
B. The mass of the piece of copper will remain same and there will be no change in its mass. However, its volume will increase, so its density will decrease.
C. This is so because heating copper in its elemental form is a physical change and there is no change in mass during a physical change. Hence, the mass of copper remain same.
Answer: reactants.
Explanation:
To the right of the arrow we have the 'after' situation. This side represents the substances that we have after the reaction has taken place. They are called the products
YER MOM.... jk, <span>Gold is used to make jewelry because
of the attractiveness of its luster and because of its rarity. It also
doesn't tarnish and doesn't react with air the way a metal like iron
does. Gold is malleable, which means it can be beaten into very thin
sheets. It's also ductile, which means it can be stretched out into thin
wire as in the findings of earrings :3</span>
<h2><u>
Answer:</u></h2>
(These are not rounded to the correct decimal)
130.94 atm
13,266.6 kPa
99,571.4 mmHg
<h2><u>
Explanation:</u></h2>
<u></u>
PV = nRT
V = 245L
P = ?
R = 0.08206 (atm) , 8.314 (kPa) , 62.4 (mmHg)
T = 273.15 + 27 = 300.15K
n = 1302.5 moles
How I found (n).
5.21kg x 1000g/1kg x 1 mole/4.0g = 1302.5 moles
Now, plug all the numbers into the equation.
Pressure in atm = (1302.5)(0.08206)(300.15) / 245 = 130.94 atm (not rounded to the correct decimal)
Pressure in kPa = (1302.5)(8.314)(300.15) / 245 = 13,266.6 kPa (not rounded to the correct decimal)
Pressure in mmHg = (1302.5)(62.4)(300.15) / 245 = 99,571.4 mmHg (not rounded to the correct decimal)