The person above above above me is very very good awnswer hope this helps
Answer:
6 days
Explanation:
The following data were obtained from the question:
Original amount (N₀) = 100 mg
Amount remaining (N) = 6. 25 mg
Time (t) = 24 days
Half life (t½) =?
Next, we shall determine the decay constant. This can be obtained as follow:
Original amount (N₀) = 100 mg
Amount remaining (N) = 6. 25 mg
Time (t) = 24 days
Decay constant (K) =?
Log (N₀/N) = kt / 2.303
Log (100/6.25) = k × 24 / 2.303
Log 16 = k × 24 / 2.303
1.2041 = k × 24 / 2.303
Cross multiply
k × 24 = 1.2041 × 2.303
Divide both side by 24
K = (1.2041 × 2.303) / 24
K = 0.1155 /day
Finally, we shall determine the half-life of the isotope as follow:
Decay constant (K) = 0.1155 /day
Half life (t½) =?
t½ = 0.693 / K
t½ = 0.693 / 0.1155
t½ = 6 days
Therefore, the half-life of the isotope is 6 days
Maglev trains were created to connect Shanghai Pudong International Airport to Central Pudong. Transrapid, another name for the Maglev train is said to be the fastest train. It can run up to 270/mph in just eight minutes.
Compared to other transportation systems, Transrapid is faster and more cost effective. It has less maintaining coverage and zero sounds compared to the ordinary ones.
This kind of train is one of the most effective means of transportation. It lessens traffic and pollution caused by car emission. It also saves more time for people who are always on the go.
Answer:
C. 1.17 grams
Explanation:
- The molarity is the no. of moles of solute in a 1.0 L of the solution.
<em>M = (mass/molar mass)solute x (1000/ V)</em>
M = 0.1 M, mass = ??? g, molar mass of NaCl = 58.44 g/mol, V = 200.0 mL.
∴ mass of NaCl = (M)(molar mass)(V)/1000 = (0.1 M)(58.44 g/mol)(200.0 mL)/1000 = 1.168 g ≅ 1.17 g.
Answer:
Density of aluminum is 2.699 g/cm^3
Explanation:
Density of a given material can be defined as the mass of the substance present in a unit volume. Mathematically it can be expressed as:

Units: g/cm^3 or kg/m^3
Aluminum (Al) is one the lightest element and is known to have a density of 2.699 g/cm^3