Answer:
NH2S4. . ...............................,..
Chemical reaction: Ba(NO₃)₂ + H₂SO₄ → BaSO₄ + 2HNO₃.
V(H₂SO₄) = 250 mL ÷ 1000 mL/L = 0,25 L.
m(BaSO₄) = 0,55 g.
n(BaSO₄) = m(BaSO₄) ÷ M(BaSO₄).
n(BaSO₄) = 0,55 g ÷ 233,38 g/mol.
n(BaSO₄) = 0,00235 mol.
From chemical reaction: n(BaSO₄) : n(Ba(NO₃)₂) = 1 : 1.
n(Ba(NO₃)₂) = 0,00235 mol.
c(Ba(NO₃)₂) = n(Ba(NO₃)₂) ÷ V.
c(Ba(NO₃)₂) = 0,00235 mol ÷ 0,25 L.
c(Ba(NO₃)₂) = 0,0095 mol/L.
Answer:
C. It blocked out sunlight
Explanation:
The asteroid impact 65 million years ago was devastating for lot of the animals and plants, resulting in a mass extinction, most noticeably of the dinosaurs. The impact itself killed a lot of flora and fauna, but it was the effect afterward that was crucial. From this impact, there was so much debris propelled into the atmosphere that the sunlight got blocked. Once this happened, most of the plants died out as they were not able to perform photosynthesis. Because the plants were dying out, the herbivores were left without food, so soon they followed, and because the herbivores died out, the predators died out to because they were left without food. The winners turned out to be the small and not specialized plants and animals.
Answer:
a. N₂O₅ + H₂O ⇒ 2 HNO₃ (pentóxido de dinitrógeno + agua ⇒ ácido nítrico)
b. Na₂O + H₂O ⇒ 2 NaOH (óxido de sodio + agua ⇒ hidróxido de sodio)
Explanation:
Tenemos que balancear, por el método de tanteo, las siguientes ecuaciones químicas.
a. En la primera reacción, el pentóxido de dinitrógeno reacciona con agua para formar ácido nítrico. Es una reacción de síntesis o combinación.
N₂O₅ + H₂O ⇒ HNO₃
Podremos obtener la ecuación balanceada si multiplicamos HNO₃ por 2.
N₂O₅ + H₂O ⇒ 2 HNO₃
b. En la segunda reacción, óxido de sodio reacciona con agua para formar hidróxido de sodio. Es una reacción de síntesis o combinación.
Na₂O + H₂O ⇒ NaOH
Podremos obtener la ecuación balanceada si multiplicamos NaOH por 2.
Na₂O + H₂O ⇒ 2 NaOH