Answer:
0.0761.
0.0059.
Explanation:
Hello!
In this case, since the writing of numbers in standard notation given the scientific notation requires adding zeros to the left of the first nonzero digit, for the first number, we need to add two zeros as seven is the third digit position:
0.0761.
Next, we need to add three zeros as 5 would be the fourth digit:
0.0059.
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The melting of the ice cube indicates physical change has taken place
Answer:
2.8M
Explanation:
The following data were obtained from the question:
Volume of stock solution (V1) = 40mL
Molarity of the stock solution (M1) = 7M
Volume of diluted solution (V2) = 100mL
Molarity of diluted solution (M2) =?
Using the dilution formula, we can easily find the molarity of the diluted solution as follow:
M1V1 = M2V2
7 x 40 = M2 x 100
Divide both side by 100
M2 = (7 x 40)/100
M2 = 2.8M
Therefore, the molarity of the diluted solution is 2.8M
Answer:
14 OH⁻(aq) + 2 Cr³⁺(aq) = Cr₂O₇²⁻(aq) + 7 H₂O(l) + 6 e⁻
Explanation:
In order to balance a half-reaction we use the ion-electron method.
Step 1: Write the half-reaction
Cr³⁺(aq) = Cr₂O₇²⁻(aq)
Step 2: Perform the mass balance, adding H₂O(l) and OH⁻(aq) where appropriate
14 OH⁻(aq) + 2 Cr³⁺(aq) = Cr₂O₇²⁻(aq) + 7 H₂O(l)
Step 3: Perform the electric balance, adding electrons where appropriate
14 OH⁻(aq) + 2 Cr³⁺(aq) = Cr₂O₇²⁻(aq) + 7 H₂O(l) + 6 e⁻
CI2 + 2Nal ---> 2NalCI + I2
Nal = 149.9 g/mol.
NaCI = 58.5 g/mol
2 mol Nal makes 2 mol NaCI
0.29 g Nal x ( 1 mol / 149.9 g) = 0.0019 mol NaCI
00.19 mol NaCI x ( 58.5 g / 1 mol ) 0.11 g NaCI ( 2 sig figs)
