The list of options to answer this question is:
A.kinectic energy is transformed into thermal energy.
B.electrical energy is transformed into potential energy.
C.potential energy is transformed into kinectic energy.
D.mechanical energy is transformed into chemical energy.
The answer is the option A. A.kinectic energy is transformed into thermal energy.
As you know energy cannot be lost but transformed.
When friction force acts over the tyres it increases the speed of the particles in the tyres which is thermal energy, this thermal energy increase comes from kinetic energy loss.
Explanation:
WE A është ai Në The H Përshëndetje Nme është
Answer is: a) I only.
Above critical temperature of CO₂, a gas cannot be liquefied no matter how much pressure is applied. Temperature and pressure above its critical point is called supercritical fluid and this is <span>intermediate between gaseous and liquid states.</span>
Electronegativity is the strength an atom has to attract a bonding pair of electrons to itself. When a chlorine atom covalently bonds to another chlorine atom, the shared electron pair is shared equally. The electron density that comprises the covalent bond is located halfway between the two atoms.
But what happens when the two atoms involved in a bond aren’t the same? The two positively charged nuclei have different attractive forces; they “pull” on the electron pair to different degrees. The end result is that the electron pair is shifted toward one atom.
ATTRACTING ELECTRONS: ELECTRONEGATIVITIES
The larger the value of the electronegativity, the greater the atom’s strength to attract a bonding pair of electrons. The following figure shows the electronegativity values of the various elements below each element symbol on the periodic table. With a few exceptions, the electronegativities increase, from left to right, in a period, and decrease, from top to bottom, in a family.
Electronegativities give information about what will happen to the bonding pair of electrons when two atoms bond. A bond in which the electron pair is equally shared is called a nonpolar covalent bond. You have a nonpolar covalent bond anytime the two atoms involved in the bond are the same or anytime the difference in the electronegativities of the atoms involved in the bond is very small.

Now consider hydrogen chloride (HCl). Hydrogen has an electronegativity of 2.1, and chlorine has an electronegativity of 3.0. The electron pair that is bonding HCl together shifts toward the chlorine atom because it has a larger electronegativity value.
A bond in which the electron pair is shifted toward one atom is called a polar covalent bond. The atom that more strongly attracts the bonding electron pair is slightly more negative, while the other atom is slightly more positive. The larger the difference in the electronegativities, the more negative and positive the atoms become.
Now look at a case in which the two atoms have extremely different electronegativities — sodium chloride (NaCl). Sodium chloride is ionically bonded. An electron has transferred from sodium to chlorine. Sodium has an electronegativity of 1.0, and chlorine has an electronegativity of 3.0.
That’s an electronegativity difference of 2.0 (3.0 – 1.0), making the bond between the two atoms very, very polar. In fact, the electronegativity difference provides another way of predicting the kind of bond that will form between two elements, as indicated in the following table.
Electronegativity DifferenceType of Bond Formed0.0 to 0.2nonpolar covalent0.3 to 1.4polar covalent> 1.5ionic
The presence of a polar covalent bond in a molecule can
Divide
Answer: 2.24 grams of Pb
Explanation:
<u>Step 1</u>
Balanced chemical reaction;
2PbS + 3O2 → 2Pb + 2SO3
<u>Step 2</u>
Moles of both PbS and O2
Moles = mass / molar mass
Moles of PbS = 2.54 g / 239.3 g/mol = 0.0108 moles
Moles of O2 = 1.88 / 32 g/mol = 0.0588 moles
<u>Step 3</u>
Finding the limiting reactant.
Limiting reactant, is that reactant which is completely used in the reaction;
If we assume that PbS is the limiting reactant;
We have 0.0588 moles of O2. This needs ( 0.0588 * 2) / 3 = 0.0392 moles of PbS to fully react. But we have only 0.0108 moles of PbS available. That means that the PbS will be completely consumed hence the limiting reactant
If we assume O2 is the limiting reactant;
We have 0.0108 moles of PbS. That needs ( 0.0108 * 3) / 2 = 0.0162 moles of O2. But we have 0.0588 moles of O2 which is in excess further confirming that PbS is the limiting reactant since it will be depleted in the reaction.
<u>Step 4</u>
Moles of lead
For this step we apply the mole ratios with the limiting reactant;
Mole ratio of PbS : Pb = 2 : 2 = 1 : 1
Therefore;
Moles of Pb = (0.0108 moles * 1 ) 1
Moles of Pb =0.0108 moles
<u>Step 5</u>
Mass of Pb
Mass = moles * molar mass
Mass of Pb =0.0108 moles * 207.2 g/mol
Mass of Pb = 2.24 grams
