Since the half life of the radioactive isotope is 4,000 years, after 4,000 years the amount of the isotope would decrease by half. (Hence the name, half life.) So, after 4,000 years, there would be half of the isotope left in the fossil.
Answer:
18.2784 g
Explanation:
First we <u>convert 180 lb to kg</u>:
- 180 lb * 0.453 kg / lb = 81.6 kg
Now we <u>calculate the mass of antibiotic taken in one day</u>:
- 8.0 mg/kg * 81.6 kg = 652.8 mg
Given that it is taken twice daily, <em>in one day the person would take (652.8 * 2) 1305.6 mg</em>. In grams that mass would be:
- 1305.6 mg / 1000 = 1.3056 g
Finally we multiply those 1.3056 daily grams by the 14 days in two weeks:
- (1.3056 g) * 14 = 18.2784 g
Answer:
Calcium oxide: CaO
Copper (II) nitrate: Cu(NO₃)₂
Ammonium chloride: NH₄Cl
Magnesium sulfate: MgSO₄
Copper (I) oxide: Cu₂O
Calcium chloride: CaCl₂
Explanation:
Hello there!
In this case, according the IUPAC rules for naming this inorganic salts, whereas calcium, copper (II), ammonium, magnesium and copper (I) are the cations and oxide, nitrate, chloride and sulfate are the anions, we proceed as follows:
Calcium oxide: CaO
Copper (II) nitrate: Cu(NO₃)₂
Ammonium chloride: NH₄Cl
Magnesium sulfate: MgSO₄
Copper (I) oxide: Cu₂O
Calcium chloride: CaCl₂
Best regards!
Answer:
2. The glassware was not dried before use
4. The Magnesium ribbon was not wiped clean before use
Explanation:
Necessary precautions are required to be taken in the laboratory when Benzophenone reacts with phenylmagnesiumbromide in ether solution to produce Triphenylmethanol. Such precautions include proper drying of any glasswares used as well as the use of tight sealing glasswares during this experiment to ensure that the Grignard reaction is free of any traces of water or moisture. Any presence of moisture during the reaction would result in a decrease in the yield of triphenylmethanol produced thereby resulting in the decrease of the effectiveness of the Grignard reaction.
Answer:
As the y-intercept increases, the graph of the line shifts up;
As the y-intercept decreases, the graph of the line shifts down
Explanation:
There are two ways to think about this problem. The first way would be the graphical approach:
- if we only change the y-intercept, this means we keep the same slope;
- y-axis is the vertical axis;
- if we change the point at which the line crosses the y-axis, we either shift it upward for a higher y-intercept or downward for a lower y-intercept.
Now, thinking algebraically, a line has the following equation in a general form:
The y-intercept is essentially obtained when x = 0, then:
y = b:
- if we increase b value, the y value increases, so the graph shifts upward;
- if we decrease b value, the y value decreases, so the graph shifts downward.
