Answer:
0.311 mmol/L
Explanation:
109 μmol = 109*10^(-6) mol
109*10^(-6) mol = 109*10^(-6) mol*(10^3 mmol/1mol) = 109*10^(-3) mmol =
=0.109 mmol
350 mL = 0.350 L
0.109 mmol/0.350 L = 0.311 mmol/L
Group 1-lose 1; Group 2-lose 2; Group 13-lose 3; Group 16-gain 2; Group 17-gain 1; Group 18-gain 0
Answer: determines the age of sample Carbon-14 is used in radiocarbon dating and radiolabeling. Medically important, a radioactive isotope is carbon-14, which is used in a breath test to determine the ulcer-causing bacteria Heliobacter pylori
The radiocarbon age of a certain sample of unknown age can be determined by measuring its carbon 14 content and comparing the result to the carbon-14 activity in modern and background samples.
To determine the number of formula units in a sample of a compound you need to divide the number of grams by the formula mass. The formula mass of NaCl is 23 g/mol + 35.5 g/mol = 58.5 g/mol, and the number of grams of the sample is 0.14 mg * 1 g/ 1000 mg = 0.00014 g. Then the answer is 0.00014 g / 58.5 g = 2.30 * 10^ -6, which rounded to two significant figures is 2.4 * 10^ -6. So<span> the answer is 2.4 * 10^-6 or 0.0000024</span>
Answer:
–1647.45 J
Explanation:
From the question given above, the following data were obtained:
Mass (M) = 112.5 g
Initial temperature (T₁) = 12.5 °C
Final temperature (T₂) = 9°C
Specific heat capacity (C) = 4.184 J/g°C
Heat (Q) absorbed =?
Next, we shall determine the change in temperature. This can be obtained as follow:
Initial temperature (T₁) = 12.5 °C
Final temperature (T₂) = 9°C
Change in temperature (ΔT) =?
ΔT = T₂ – T₁
ΔT = 9 – 12.5
ΔT = –3.5 °C
Finally, we shall determine the heat absorbed. This can be obtained as follow:
Mass (M) = 112.5 g
Change in temperature (ΔT) = –3.5 °C
Specific heat capacity (C) = 4.184 J/g°C
Heat (Q) absorbed =?
Q = MCΔT
Q = 112.5 × 4.184 × –3.5
Q = –1647.45 J