Answer: False
Explanation:
In chemical reactions new substances are formed.
Answer:
8.8g of Al are necessaries
Explanation:
Based on the reaction, 2 moles of Al are required to produce 3 moles of hydrogen gas.
To solve this question we must find the moles of H2 in 11L at STP using PV = nRT. With these moles we can find the moles of Al required and its mass as follows:
<em>Moles H2:</em>
PV = nRT; PV/RT = n
<em>Where P is pressure = 1atm at STP; V is volume = 11L; R is gas constant = 0.082atmL/molK and T is absolute temperature = 273.15K at STP</em>
Replacing:
1atm*11L/0.082atmL/molK*273.15K = n
n = 0.491 moles of H2 must be produced
<em />
<em>Moles Al:</em>
0.491 moles of H2 * (2mol Al / 3mol H2) = 0.327moles of Al are required
<em />
<em>Mass Al -Molar mass: 26.98g/mol-:</em>
0.327moles of Al * (26.98g / mol) = 8.8g of Al are necessaries
Compressibility refers to the amount or extent to which a substance can be compressed, also involving the the relationship between changes in volume due to applied pressure.
Answer:
Astronomers use radar measurements, telemetry and exploration of solar system to get precise measurement of astronomical units.
Astronomers use parallax techniques. They measure the distance between the Earth and solar planets. Astronomers use parallax techniques to conduct parallax measurements which gave them accurate and precise values of the length of astronomical units
Explanation:
Astronomical unit is a unit length which is the average distance between the Earth and the sun which is about 150 millions kilometers.
Astronomers use radar measurements, telemetry and exploration of solar system to get precise measurement of astronomical units.
Astronomers use parallax techniques. They measure the distance between the Earth and solar planets. Astronomers use parallax techniques to conduct parallax measurements which gave them accurate and precise values of the length of astronomical units.
Explanation:
<h3>Because melting point and freezing point describe the same transition of matter, in this case from liquid to solid (freezing) or equivalently, from solid to liquid (melting). It is stuck on 0 ∘C during the entire melting or freezing process. None except melting is when you heat up and freezing when you cool down.</h3>
<h2>hope it helps.</h2><h2>stay safe healthy and happy.</h2>
