Answer:
Explanation:
The law of conservation of mass states that "mass in a system remains constant and that the mass of the product is remains the same as that of the reactants".
Law of conservation of energy states that "energy is neither created nor destroyed in the course of chemical or physical change but can be transformed from one form to another".
Let us properly write the equation:
CH₄ + 2O₂ → CO₂ + 2H₂O
For the conservation of mass:
C has 1mole on both sides
H has 4mole on both sides
O has 4 mole on both sides
For energy, during combustion process, the methane CH₄ burns to liberate heat energy. This is an energy conversion process in which chemical energy in methane releases heat energy.
Igneous rocks are found where plates diverge, as lava rises and fills the gap between the plates. Igneous rocks also form where plates converge. The subducting plate melts as it sinks into the crust of the Earth, and the melt rises into the overriding plate forming volcanoes.
Answer: fourth option, 10.8 kJ
Explanation:
The <em>heat of fusion</em>, also named latent heat of fusion, is the amount of heat energy required to change the state of a substance from solid to liquid (at constant pressure).
The data of the <em>heat of fusions</em> of the substances are reported in tables and they can be shown either per mole or per gram of substance.
In this case we have that the<em> heat of fusion for water </em>is reported per mole: <em>6.02 kJ/mole</em>.
The formula to calculate <em>how many kJ of heat (total heat) are needed to completely melt 32.3 g of water, given that the water is at its melting point</em> is:
- Heat = number of moles × heat of fusion
The calculations are:
- number of moles = mass / molar mass
number of moles = 32.3 g / 18.015 g/mol = 1.79 mol
- Heat = 1.79 mol × 6.02 kJ / mol = 10.8 kJ ← answer
Answer:
D. It is converted into kinetic energy.
Explanation:
When a book is dropped from a desk to the floor, the potential energy of the book is converted to kinetic energy as it falls.
- Potential energy of a body is the energy due to the position of the body.
- At a particular height, the potential energy is maximum.
- A body with mass and moving with velocity will have kinetic energy
- As the book drops through the height, to conserve energy, the potential energy is converted to kinetic energy.
Answer: Water is a permanent electric dipole, having permanent charge separation.
Explanation:
Hydrogen bonding is an intermolecular force having partial ionic-covalent character.
In 
, O is a highly electronegative atom attached to a H atom through a covalent bond. The oxygen atoms being more electronegative gets partial negative charge and H atom gets partial positive charge. Thus water is permanent electric dipole.
Hydrogen bonding takes place between a hydrogen atom (attached with an electronegative atom O) and an electronegative atom (O).
