Summer days are warmer because the path of the sun is longer and we have more direct sunlight during that time
Answer:
I <em>believe</em> it is Avogadro's number: 6.022 × 10²³
Explanation:
One mole of a substance is equal to 6.022 × 10²³ units of that substance
Answer:
The formula of the original halide is SrCl₂.
Explanation:
- The balanced equation of this reaction is:
SrX₂ + H₂SO₄ → SrSO₄ + 2 HX, where X is the halide.
- From the equation stichiometry, 1.0 mole of strontium halide will result in 1.0 mole of SrSO₄.
- The number of moles of SrSO₄ <em>(n = mass/molar mass) </em>= (0.755 g) / (183.68 g/mole) = 4.11 x 10⁻³ mole.
- The number of moles of SrX are 4.11 x 10⁻³ moles from the stichiometry of the balanced equation.
- n = mass / molar mass, n = 4.11 x 10⁻³ moles and mass = 0.652 g.
- The molar mass of SrX₂ = mass / n = (0.652) / (4.11 x 10⁻³ moles) = 158.62 g/mole.
- The molar mass of SrX₂ (158.62 g/mole) = Atomic mass of Sr (87.62 g/mole) + (2 x Atomic mass of halide X).
- The atomic mass of halide X = (158.62 g/mole) - (87.62 g/mole) / 2 = 71 / 2 g/mole = 35.5 g/mole.
- This is the atomic mass of Cl.
- <em>So, the formula of the original halide is SrCl₂</em>.
Answer:
- C. it is a strong acid since the blue litmus paper turns red and the pH is 1.7
Explanation:
As per table gastric juice has pH of 1.7 which is the strong acid. If you remember, 0-7 range determines acids and litmus paper confirms that by turning red.
So correct choice is C.
Answer:
Extinction event or sometimes known as Mass extinction
Explanation:
These events typically are typically widespread and rapid decrease in the biodiversity (which takes into account spread and existence of current species). The worst mass extinction was Permian–Triassic extinction where over 90% of species of organisms vanished.