Answer:
0.87 pg
Explanation:
<em>GenAlex Medical, a leading manufacturer of medical laboratory equipment, is designing a new automated system that can detect normal levels of dissolved triiodothyronine (230. to 660 pg/dL), using a blood sample that is as small as 380 μL. Calculate the minimum mass in picograms of triiodothyronine that the new system must be able to detect. Be sure your answer has the correct number of significant digits.</em>
Step 1: Convert 380 μL to deciliters
We will use the following conversion factors.
380 μL × 1 L/10⁶ μL × 10 dL/1 L = 3.8 × 10⁻³ L
Step 2: Calculate the minimum mass of triiodothyronine that can be found in a 3.8 × 10⁻³ L blood sample
Since we are looking for the minimum mass, we will use the lower limit of the concentration interval (230. pg/dL).
3.8 × 10⁻³ L × 230. pg/dL = 0.87 pg
Answer:
A. The energy stored in atmospheric carbon dioxide is conserved because it is used to create new forms of energy present in decomposed plants.
Explanation:
In the carbon cycle image, the result of an industry's work releases carbon dioxide into the atmosphere (this is represented by the letter G), this carbon dioxide is stored in the atmosphere (letter C) and then absorbed by plants during the process. of photosynthesis (letter A).
The carbon cycle is constituted by the absorption of carbon dioxide by plants in the photosynthesis process. Half of this absorbed carbon is released into the atmosphere and the other half the vegetable uses to produce sugars (glycoses). By ingesting the plants, the animals ingest together the carbon to their body, being released through respiration or decomposition. Because some fungi and bacteria are responsible for the decomposition of both animals and vegetables, they ingest part of this carbon, releasing it into the atmosphere and soil. In addition to bacteria, the burning process also releases carbon dioxide into the soil and atmosphere. Vegetables, through the breathing process, also absorb carbon dioxide and release oxygen unlike animals.
Answer: False
Explanation: The nucleus of an atom only contains the protons and neutrons.
The electrons are not found in the nucleus,
they are orbiting the nucleus in different shells.
Answer:
0.15g
Explanation:
Given parameters:
Number of molecules of water = 1.2 x 10²¹ molecules
Unknown:
Mass of SnO₂ = ?
Solution:
To solve this problem, we have to work from the known to the unknown specie;
SnO₂ + 2H₂ → Sn + 2H₂O
Ensure that the equation given is balanced;
Now,
the known species is water;
6.02 x 10²³ molecules of water = 1 mole
1.2 x 10²¹ molecules of water = 
= 0.2 x 10⁻²moles
Number of moles of water = 0.002moles
From the balanced chemical equation:
2 mole of water is produced from 1 mole of SnO₂
0.002 moles of water will be produced from 
= 0.001moles
To find the mass;
Mass = number of moles x molar mass
Molar mass of SnO₂ = 118.7 + 2(16) = 150.7g/mol
Mass = 0.001 x 150.7 = 0.15g
