B the atmosphere
D. gasoline
C. a carbonated soft drink (without bubbles)
Answer: Thus 0.724 mol of 
are needed to obtain 18.6 g of 
Explanation:
To calculate the moles :
According to stoichiometry :
2 moles of are produced by = 1 mole of
Thus 1.09 moles of will be produced by =
of
But as yield of reaction is 75.6 %, the amount of needed is =
Thus 0.724 mol of are needed to obtain 18.6 g of
Biodiversity has a fundamental value to humans because we are so dependent on it for our cultural, economic, and environmental well-being. Some argue that it is our moral responsibility to preserve the Earth’s incredible diversity for the next generation. Others simply like knowing that nature’s great diversity exists and that the opportunity to utilize it later, if need be, is secure. Scientists value biodiversity because it offers clues about natural systems that we are still trying to understand. Arguably, the greatest value to humans, however, comes from the ?ecosystem services? it provides.
Biodiversity forms the backbone of viable ecosystems on which we depend on for basic necessities, security, and health. By breaking down plant and animal matter, for example, insects and other invertebrates make nutrients available to plants and are integral to the carbon and nitrogen cycles. Other species pollinate crops, an essential service for farmers. Healthy ecosystems can mitigate or prevent flooding, erosion, and other natural disasters. These ecosystem services also play a hand in the functioning of our climate and in both air and water quality.
CATGGATCCA for future reference this is considered biology, you may get a quicker response if you categorize it as such :)
The initial mass of sodium hydroxide is 3.3 g (answer C)
<u><em>calculation</em></u>
Step 1 : find the moles of iron (ii) hydroxide ( Fe(OH)₂
moles = mass÷ molar mass
from periodic table the molar mass of Fe(OH)₂ = 56 + [16 +1]2 = 90 g/mol
moles is therefore = 3.70 g÷ 90 g/mol = 0.041 moles
Step 2: use the mole ratio to calculate the moles of sodium hydroxide (NaOH)
from given equation NaOH : Fe(OH)₂ is 2 :1
therefore the moles of NaOH = 0.041 x 2 = 0.082 moles
Step 3: find mass of NaOH
mass = moles x molar mass
from the periodic table the molar mass of NaOH = 23 +16 +1 = 40 g/mol
mass = 0.082 moles x 40 g/mol = 3.3 g ( answer C)
