Answer:
Demonstration 1 showed a chemical change because a new gaseous substance was formed, and demonstration 2 showed a physical change because liquid water became water vapor.
Explanation:
Chemical changes alter the chemical makeup of a subject, and a physical change only alters the appearance of a subject, not the chemical makeup.
Answer:
pH = 11.60
Explanation:
When we add a base, we are increasing [OH⁻], so the pH will be totally basic.
pH of water = 7
Basic pH > 7
We are adding 2 M . 1 mL = 2 mmoles
2 mmoles of OH⁻ are contained in 501 mL of total volume.
[OH⁻] = 2 mmol / 501 mL = 3.99×10⁻³ M
- log 3.99×10⁻³ M = 2.39 → pOH
pH = 14 - pOH → 11.61
Water equilibrium
2H₂O ⇄ H₃O⁺ + OH⁻ Kw = 1×10⁻¹⁴
NaOH → Na⁺ + OH⁻
Answer:
It increases endurance, builds muscle to maintain an optimal body fat composition, promotes cardiovascular health, strengthens the heart, and even improves your overall mood. Combined with weight training, running can help you maintain the perfect balance of mental stimulation and physical fitness.
Explanation: