Answer: D
Explanation:
This is the answer because everyone knows he discovered gravity and he conducted scientific experiments to prove them which he also used math for
Hope this helps
You have to calculate the oxidation estates of the atoms in each compound.
I will start with K2Cr2O7 because I believe that Cr is the best candidate to reduce its oxidation number in 3 units.
In K2Cr2O7:
- K has oxidation state of 1+, then K2 has a charge of 2* (1+) = 2+.
- O has oxidation state of 2*, then O7 has a charge of 7* (2-) = 14-.
That makes that Cr2 has charge of 14 - 2 = +12, so each Cr has +12/2 = +6 oxidation state.
In Cr2O3:
- O has oxidation state of 2-, then O3 has charge 3 * (2-) = - 6
- Then, Cr2 has charge 6+, and each Cr has charge 6+ / 2 = 3+.
So, we have seen that Cr reduced its oxidation state in 3 units, from 6+ to 3+.
Answer: Cr has a change in oxidation number of - 3.
Answer:
helium hydrogen
Explanation:
lithium beryllium bottom carbon
Answer:
V = 22.41 L
Explanation:
Given data:
Mass of nitrogen = 14.0 g
Volume of gas at STP = ?
Gas constant = 0.0821 atm.L/mol.K
Solution:
Number of moles of gas:
Number of moles = mass/molar mass
Number of moles= 14 g/ 14 g/mol
Number of moles = 1 mol
Volume of gas:
PV = nRT
1 atm × V = 1 mol × 0.0821 atm.L/mol.K × 273 K
V = 22.41 atm.L / 1 atm
V = 22.41 L
Explanation:
A physical change is one that alters the physical properties of matter (particularly the form and state).
A chemical change is one in which new kind of matter is formed. It is always accompanied by energy changes (evolution or absorption of energy in form of heat or light or both).
Now, the salient differences between physical and chemical changes;
- Physical changes are easily reversible whereas chemical changes are not easily reversible.
- Physical changes lead to the production of no new kinds of matter whereas chemical changes leads to the production of new kinds of matter.
- Physical changes involves no change in mass whereas chemical changes involves change in mass.
- Physical changes require little energy whereas considerable amount of energy is needed for chemical changes.