Answer:
4 is the answer
Explanation:
i am not sure for this question
All chemical reaction between substances results into a chemical change. When two substances just like HCL and NaOH reacts with each other, NaCl means Sodium Chloride salt is formed.
The phenomenon like change in color, change in temperature, release of gas etc when happens ,then it means chemical change has been occurred. e.g
HCl +NaOH ----> NaCl +H2O.
Answer:
0.456 M
Explanation:
Step 1: Write the balanced neutralization equation
HNO₂ + KOH ⇒ KNO₂ + H₂O
Step 2: Calculate the reacting moles of KOH
9.26 mL of 1.235 M KOH react.
0.00926 L × 1.235 mol/L = 0.0114 mol
Step 3: Calculate the reacting moles of HNO₂
The molar ratio of HNO₂ to KOH is 1:1. The reacting moles of HNO₂ are 1/1 × 0.0114 mol = 0.0114 mol.
Step 4: Calculate the initial concentration of HNO₂
0.0114 moles of HNO₂ are in 25.0 mL of solution.
[HNO₂] = 0.0114 mol / 0.0250 L = 0.456 M
The amu is a unit which means the mass per neutron, So the 74.55 means the mass per mole KCl. So the mole number of 2.330g KCl is 2.330/74.55=0.031 mol. The volume is 0.031/0.1250=0.248 L ≈ 250 mL. So the answer is a.
