Buffer is formed from weak acid and its salt with strong base (its conjugate base)
So the only one correct answer is :
0.2 M H₃PO₄ and 0.2 M NaH₂PO₄
While all other choices are incorrect
Answer: There must be the same number of atoms of each element on both sides of the equation.
Explanation: This is the only way the equations will be balanced. Adding the coefficients to see if they are equal will not guarantee that the equations are balanced becuase coefficients can be turned into subscripts.
Explanation:
: of or relating to the partitioning and cycling of chemical elements and compound's between the living and nonliving part's of an ecosystem.
I believe the answer is A. <span>make a softer sound because the shark will not hear the softer signal.
</span><span>
I say this becasue "</span><span>Some of the sounds dolphins make are outside the range of human hearing." So that means the the dolphins speak at a higher wavelength then us humans and we can't hear it so they could use that to their advantage and speak at a height wavelength to each other when sharks are near.
I could be wrong, but I think the answer is A. </span>
Answer:
96.31 g.
Explanation:
- From the balanced reaction:
<em>CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O,</em>
1.0 mole of CaCO₃ reacts with 2.0 moles of HCl to produce 1.0 mole of CaCl₂, 1.0 mole of CO₂, and 1.0 mole of H₂O.
- We need to calculate the no. of moles of (104 g) of CaCO₃:
<em>no. of moles of CaCO₃ = mass/molar mass </em>= (102 g)/(100.08 g/mol) = <em>1.019 mol.</em>
<u><em>Using cross multiplication:</em></u>
1.0 mole of CaCO₃ produce → 1.0 mole of CaCl₂.
∴ 1.019 mole of CaCO₃ produce → 1.019 mole of CaCl₂.
∴ The amount of CaCl₂ produced = no. of moles x molar mass = (1.019 mol)(110.98 g/mol) = 113.1 g.
∵ percent yield of the reaction = [(actual yield)/(theoretical yield)] x 100.
Percent yield of the reaction = 85.15%, theoretical yield = 113.1 g.
<em>∴ actual yield = [(percent yield of the reaction)(theoretical yield)]/100</em> = [(85.15%)(113.1 g)] / 100 = <em>96.31 g.</em>
