D
Molecules consist of multiple atoms put together to create a new form.
Answer: 4.96 moles
Explanation:
C5H12 is the chemical formula for pentane, the fifth member of the alkane family.
Given that,
number of moles of C5H12 = ?
Mass in grams = 357.4 g
Molar mass of C5H12 = ?
To get the molar mass of C5H12, use the atomic mass of carbon = 12g; and Hydrogen = 1g
i.e C5H12 = (12 x 5) + (1 x 12)
= 60g + 12g
= 72g/mol
Now, apply the formula
Number of moles = Mass / molar mass
Number of moles = 357.4g / 72g/mol
= 4.96 moles
Thus, 4.96 moles of C5H12 that are contained in 357.4 g of the compound.
Answer:
2Ca + O₂ → 2CaO
Explanation:
Cuando el Calcio (Ca) reacciona con oxígeno (O₂) se produce cal (CaO). La cal es un sólido inodoro de color blanco a grisáceo. La cal es un óxido que se encuentra presente en el cemento y su cuantificación permite determinar la calidad y el tipo de cemento a utilizar.
La reacción que describe el proceso anterior es:
Ca + O₂ → CaO
Para balancear los oxígenos, se deben poner 2 CaO como producto:
Ca + O₂ → 2CaO
Para balancear los calcios, se pone como coeficiente del Ca un 2:
<h3>2Ca + O₂ → 2CaO</h3><h3 />
Esta última es la reacción que describe el proceso anterior
Na2+(answer B) represent ions.
<h3>Explanation</h3>
This is because it has a charge of 2+. ion is formed when an atom gain or lose electrons. when an atom lose electrons it form ion which is positively charged . On the other hand when atom gain electrons it forms ion of negatively charged. Na2+ has a charge of 2+ since it loses two electrons.
