Answer:Chemistry is important for meeting our needs of food,clothing,shelter,health,energy,and clan air,water,and soil.
Answer:
1L
Explanation:
First, let us calculate the number of mole present in 20g of NaOH. This is illustrated below:
Mass = 20g
Molar Mass of NaOH = 23 + 16 + 1 = 40g/mol
Number of mole =?
Number of mole = Mass /Molar Mass
Number of mole of NaOH = 20/40 = 0.5mol
From the question given, we obtained the following data:
Molarity = 0.5M
Mole = 0.5mole
Volume =?
Molarity = mole /Volume
Volume = mole /Molarity
Volume = 0.5/0.5
Volume = 1L
1. The hypothesis for this is experiment is that the 50:50 of methanol-water mixture will not turn to solid when the temperature reaches to -40°C.
2. The procedure for this is measuring equal volumes of water and methanol using the graduated cylinder. You can measure 100 mL of water and 100 mL of methanol using the graduated cylinder. Then, mix them in the beaker. Next, measure 200 mL of water, and another 200 mL of methanol. Don't mix them. Also, make a 60:40 mixture by measuring 120 mL of water and 80 mL of methanol, then mix them together. Place them all in the refrigerator at the same time. Record the time when they would freeze to solid.
3. The controls for this experiment are the 200 mL water alone, and the 200 mL methanol alone.
4. The independent variable in here is the time, while the dependent variable is the temperature of the mixtures.
5. If the hypothesis turns out to be true, then all the mixtures prepared should freeze and become solid after a certain period of time, with the exception of the 50:50 mixture. The 50:50 mixture should still remain as a liquid even when left overnight.
Answer:
this was the last of .the last 555543 years of 55my in
Explanation:
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Answer:
a. A beta particle has a negative charge. d. A beta particle is a high-energy electron.
Explanation:
Identify the correct descriptions of beta particles.
a. A beta particle has a negative charge. YES. A beta particle is originated in the following nuclear reaction: ¹₀n ⇒ ¹₁H + ⁰₋₁e (beta particle.)
b. A beta particle contains neutrons. NO. It is a electron originated in the nucleus.
c. A beta particle is less massive than a gamma ray. NO. Gamma rays don't have mass while a beta particle has a mass which is half of one thousandth of the mass of a proton.
d. A beta particle is a high-energy electron. YES. Beta particles are nuclear originated hig-energy electrons.
