Answer:
B.Thermal insulation minimizes energy loses to the atmosphere.
Explanation:
It is important because it helps to stop hit from transferring from the calorimeter to the environment. This would help to have an accurate measurement of the heat that was used in the chemical process. The greatest cause of error that happens in calorimetry is when heat is lost to the environment. To reduce this, you insulate the calorimeter and add a cover.
Mass is a basic property of matter and is made of atoms. Atoms are made of electrons, protons, and neutrons. Protons and neutrons make up the majority of the mass in an atom. Atoms may vary in the number of neutrons they have (called isotopes), and therefore the exact atomic mass may vary from atom to atom
Answer:
The lung
Explanation:
The model of the respiratory system made by Megan consists of two balloons. The first balloon stretched across the bottom of the bottle represents the diaphragm which contracts and relaxes to allow air in and out of the lungs. The balloon inside the bottle represents one lung.
Breathing in causes the balloon inside the bottle to be filled with air. This is preceded by the expansion of the diaphragm which makes the lungs to be filled with air. Breathing out causes a contraction of the diaphragm thus making the lungs to let out air.
Science is a continuous profession of study because new ideas are produced based on new evidence. Also, there are different topics of science such as climate change or new cures to different diseases.
Answer:
[HF]₀ = 0.125M
Explanation:
NaOH + HF => NaF + H₂O
Adding 20ml of 0.200M NaOH into 25ml of HF solution neutralizes 0.004 mole of HF leaving 0.004 mole NaF in 0.045L with 0.001M H⁺ at pH = 3. This is 0.089M NaF and 0.001M HF remaining.
=> 45ml of solution with pH = 3 and contains 0.089M NaF from titration becomes a common ion problem.
HF ⇄ H⁺ + F⁻
C(eq) [HF] 10⁻³M 0.089M (<= soln after adding 20ml 0.200M NaOH)
Ka = [H⁺][F⁻]/[HF]₀ => [HF]₀ = [H⁺][F⁻]/Ka
[HF]₀ = (0.001)(0.089)/(7.1 x 10⁻⁴) M = 0.125M
