Answer:
Usually light years, or parsecs.
Explanation:
Okay so we are given these requirements:
element which can be used to stuff
bottles that enclose ancient paper
must be a gas at room temperature
must be denser than helium
must not react with other elements
The only element that comes into my
mind is:
<span>Argon</span>
The elements in each pair have in common it that they are metaloids
Answer:
164.3g of NaCl
Explanation:
Based on the chemical equation:
CaCl2 + 2NaOH → 2NaCl + Ca(OH)2
<em>where 1 mole of CaCl2 reacts with 2 moles of NaOH</em>
To solve this question we must convert the mass of CaCl2 to moles. Using the chemical equation we can find the moles of NaCl and its mass:
<em>Moles CaCl2 -Molar mass: 110.98g/mol-</em>
156.0g CaCl₂ * (1mol / 110.98g) = 1.4057 moles CaCl2
<em>Moles NaCl:</em>
1.4057 moles CaCl2 * (2mol NaCl / 1mol CaCl2) = 2.811 moles NaCl
<em>Mass NaCl -Molar mass: 58.44g/mol-</em>
2.811 moles NaCl * (58.44g / mol) = 164.3g of NaCl
A. actinides do not occur in nature.
