Experiments test the scientists' ideas.
Answer:
A) in response to an increase in the cytoplasmic Ca2+concentration.
Explanation:
Muscle contraction occurs in response to an increase in the cytoplasmic Ca2 + concentration.
This process occurs with the shortening of the sarcomeres resulting in a result, the actin filaments react with myosin, generating actomyosin. During this reaction, it is necessary to increase the cytoplasmic concentration of Ca + and ATP. In this, myosin will break down ATP, releasing energy so that the muscle can contract.
Answer:
3.4
Explanation:
The pH scale is used to express the acidity or basicity of a solution.
- If the pH < 7, the solution is acid.
- If the pH = 7, the solution is neutral.
- If the pH > 7, the solution is basic.
Given the hydronium ion concentration [H₃O⁺] = 3.8 × 10⁻⁴ M, we can calculate the pH using the following expression.
pH = -log [H₃O⁺]
pH = -log 3.8 × 10⁻⁴
pH = 3.4
This solution is acid.
The increase in the boiling point of a solvent is a colligative property.
That means that the increase in the boling point will be related to the number of particles (molecules or ions) present in the solution.
The higher the number of particles (molecules or ions) the higher the increase in the boiling point.
All the aqueous solutions presented are electrolytes, i.e. the solutes are ionic compounds.
Then, you have to compare the number of ions that you have in each solution.
A) 1.0 M KCl ---> 1.0 M K+ + 1.0 MCl- = 2 moles of particles / liter
B) 1.0 M CaCl2 --> 1.0M Ca(2+) + 1.0M * 2 Cl (-) = 3 moles of particle / liter
C) 2.0M KCl ---> 2.0 M K+ + 2.0 M Cl- = 4 moles of particle / liter
D) 2.0 M CaCl2 ----> 2.0 M Ca (2+) + 2.0M * 2 Cl (-) = 6 moles of particle / liter.
Then, the solution 2.0M CaCl2(aq) has the highest increase in the boiling point.
Answer: option D) 2.0 M Ca Cl2(aq)