Answer:
98.68%
Explanation:
Step 1: Write the balanced equation
KBr + AgNO₃ ⇒ AgBr + KNO₃
Step 2: Calculate the moles corresponding to 814.5 mg (0.8145 g) of AgBr
The molar mass of AgBr is 187.77 g/mol.
0.8145 g × 1 mol/187.77 g = 4.338 × 10⁻³ mol
Step 3: Calculate the moles of KBr needed to produce 4.338 × 10⁻³ moles of AgBr
The molar ratio of KBr to AgBr is 1:1. The moles of KBr needed are 1/1 × 4.338 × 10⁻³ mol = 4.338 × 10⁻³ mol.
Step 4: Calculate the pure mass corresponding to 4.338 × 10⁻³ moles of KBr
The molar mass of KBr is 119.00 g/mol.
4.338 × 10⁻³ mol × 119.00 g/mol = 0.5162 g
Step 5: Calculate the purity of KBr
0.5162 g of KBr are in a 0.5231 g-sample. The purity of KBr is:
P = 0.5162 g/0.5231 g × 100% = 98.68%
Relative dating is the process of determining whether an object or event is older or younger than other objects or events. Absolute dating is d<span>etermining the age of an event or object in years. From absolute dating, the real age of the object is obtained which is not present for relative dating. Hope this helps.</span>
1.7 km^2 already has two significant figures.
Answer:
Regeneration of NAD+
Explanation:
Glycolysis is an inefficient process to produce ATP, but it has been crucial for survival of different kind of cells, and is a step previous in aerobic respiration, where carbohydrates are completely oxidized producing much more ATP molecules.
Both alcoholic and lactic acid fermentations, generate ATP from glycolysis. NADH is also produced in glycolysis, and is used to reduce piruvic acid (glycolysis end product) direct or indirectly in these fermentations. Directly, piruvic acid is reduced by NADH to produce lactic acid in lactic acid fermentation. Indirectly, reducing acetaldehyde (product of previous piruvic acid decarboxilation) into ethanol, in alcohol fermentation.
In both fermentations NAD+ is regenerated, to be used in another round of glycolysis