Answer:
Communication between scientists increased.
Technological advancements were made.
Explanation:
The options:
<em> Metalworkers began using new metals.
</em>
<em> Communication between scientists increased.
</em>
<em> The American Civil War started.
</em>
<em> Technological advancements were made.</em>
<u>The reasons the number of known elements more than double by 1861 would be because technological advancements have been made and communication between scientists increased.</u>
With the advancement in technology, more equipment become available and research became more sophisticated leading to new discoveries. The new discoveries would not have made much difference if they are not adequately communicated to other scientists.
Answer:
Explanation:
The limiting reactant (or limiting reagent) is the reactant that gets consumed first in a chemical reaction and therefore limits how much product can be formed.
<span>Step 1: find number of moles of Mg(divide 4.03 by its molor mass)
step 2:find number of moles in O2
step 3: remember STP is 22.4 L = 1 mole</span>
step 4: multiply 0.0829mol O₂ by 22.4L/mol to get 1.857L
answer is 1860 mL
Answer:
13.7 moles
Explanation:
Given data:
Number of moles calcium carbonate = ?
Formula units calcium carbonate= 8.23 × 10²⁴
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 8.23 × 10²⁴ formula units:
one mole = 6.022 × 10²³ formula units
8.23 × 10²⁴ formula units × 1 mole /6.022 × 10²³ formula units
13.7 moles
