102 grams.
Equation:
Quantify of heat = mass x specific heat x difference in temperature
We have: quantity of heat : 2300J
specific heat: .449 J/g
difference in t: 80 - 30 = 50
Solve for mass: 2300 = mass x 0.449 x 50
mass = 102.449
2 sig-figs --> 102 grams
Answer: C) a redox reaction that produces an electric current
Explanation:
Chemical cell is a device which is used for the conversion of the chemical energy produced in a redox reaction into the electrical energy. The cell consists of the negative terminal called as anode where oxidation takes place and a positive terminal called as cathode where reduction takes place.
Electrolytic cell is a device which is used to carry out chemical reactions by the use of electrical energy. The cell consists of the negative terminal called as cathode where reduction takes place and a positive terminal called as anode where oxidation takes place.
The rules of base pairing (or nucleotide pairing) are: A with T: the purine adenine (A) always pairs with the pyrimidine thymine (T) C with G: the pyrimidine cytosine (C) always pairs with the purine guanine (G)
The nucleotides in a base pair are complementary which means their shape allows them to bond together with hydrogen bonds. The A-T pair forms two hydrogen bonds. The C-G pair forms three. The hydrogen bonding between complementary bases holds the two strands of DNA together.
Using electronegativity difference is a good guide to the ionic/ covalent nature. Large differences indicate greater ionic character, small differences more covalent character. The larger the difference in electronegativity the more ionic properties a bond is said to have. The smaller the difference in electronegativity the more covalent properties a bond is said to have.
Ionic bonding is formed through electrostatic attraction between a cation and anion. Foe example, Sodium fluoride has ionic bonding because it is composed by sodium and Fluorine (a non metal). On the other hand, covalent bonding is characterized by atoms sharing pairs of electrons. For example; methane has covalent bonding; carbon has 4 valence electrons and hydrogen has 1; when they bond they have a total of 8 electrons and satisfies the octet rule.
Based on temperature changes, the phase changes that occur in water is from a solid at A to a liquid at B, and from liquid a B to gas at C.
<h3>What is change of state?</h3>
Change of state is the process whereby a substance changes its state of matter from one form to another as as result of heat changes.
In the graph shown above, water exists in three states at different points.
- Water exists as a solid at A
- Water exists as a liquid at B
- Water exists as a gas at C.
Therefore, the phase changes that occur in water is from a solid at A to a liquid at B, and from liquid a B to gas at C.
Learn more about change of state at: brainly.com/question/18372554
