Answer:
True
Explanation:
Friction is defined as the force that opposes motion when an object is sliding over a surface.
As a result of friction, all objects moving over a surface eventually come to rest over time.If we were to successfully create a friction-less surface, an object will remain in motion forever because it will encounter no opposition to its motion.
Hence, the resistance to the motion of objects over a surface which causes the objects to come to a halt after moving over the surface for some time is called friction.
Answer:
1. C. helium
2. D. oxygen and acetylene
3. B. deliquescence
4. C. cutting very hard surfaces
5. B. 3.5%
Explanation:
Answer:
Explanation:
<u>1) Reactants:</u>
The reactants are:
- <em>Molecular chlorine</em>: this is a gas diatomic molecule, i.e. Cl₂ (g)
- <em>Molecular fluorine</em>: this is also a gas diatomic molecule: F₂ (g)
<u>2) Stoichiometric coefficients:</u>
- <em>One volume of Cl₂ react with three volumes of F₂</em> means that the reaction is represented with coefficients 1 for Cl₂ and 3 for F₂. So, the reactant side of the chemical equation is:
Cl₂ (g) + 3F₂ (g) →
<u>3) Product:</u>
- It is said that the reaction yields <em>two volumes of a gaseous product;</em> then, a mass balance indicates that the two volumes must contain 2 parts of Cl and 6 parts of F. So, one volume must contain 1 part of Cl and 3 parts of F. That is easy to see in the complete chemical equation:
Cl₂ (g) + 3F₂ (g) → 2Cl F₃ (g)
As you see, that last equation si balanced: 2 atoms of Cl and 6 atoms of F on each side, and you conclude that the formula of the product is ClF₃.
Answer:
CaCO₃
Explanation:
Calcium ion is written as Ca²⁺
Carbonate ion is written as CO₃²¯
During bonding, the +2 ions from the calcium and the –2 ions from the carbonate will cancel out given a net charge of zero as shown below:
Ca²⁺ + CO₃²¯ —> CaCO₃
Thus, the correct formula for the ionic compound that forms when oppositely charged ions of calcium and carbonate attract is CaCO₃.
Answer:
The partial pressure of oxygen in the mixture is 296 mmHg.
Explanation:
The pressure exerted by a particular gas in a mixture is known as its partial pressure. So, Dalton's law states that the total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert if it were alone.
This relationship is due to the assumption that there are no attractive forces between the gases.
So, in this case, the total pressure is:
PT=Phelium + Pnitrogen + Poxygen
You know:
- PT= 756 mmHg
- Phelium= 122 mmHg
- Pnitrogen= 338 mmHg
- Poxygen= ?
Replacing:
756 mmHg= 122 mmHg + 338 mmHg + Poxygen
Solving:
756 mmHg - 122 mmHg - 338 mmHg = Poxygen
Poxygen= 296 mmHg
<u><em>The partial pressure of oxygen in the mixture is 296 mmHg.</em></u>
