Solid state of matter
- the atoms are tightly packed in orderly form, they slightly vibrate but are stuck in a fixed position. Solids cannot be compressed and they maintain their shape
Answer:
rebar
is gridwork of steel rods
Explanation:
Reinforced concrete is one important component of skyscrapers. It consists of concrete (a mixture of water, cement powder, and aggregate consisting of gravel or sand) poured around a gridwork of steel rods (called rebar) that will strengthen the dried concrete against bending motion caused by the wind.
<h3>The density of H₂ = 0.033 g/L</h3><h3>Further explanation</h3>
In general, the gas equation can be written
![\large {\boxed {\bold {PV = nRT}}}](https://tex.z-dn.net/?f=%5Clarge%20%7B%5Cboxed%20%7B%5Cbold%20%7BPV%20%3D%20nRT%7D%7D%7D)
where
P = pressure, atm , N/m²
V = volume, liter
n = number of moles
R = gas constant = 0.082 l.atm / mol K (P= atm, v= liter),or 8,314 J/mol K (P=Pa or N/m², v= m³)
T = temperature, Kelvin
n = N / No
n = mole
No = Avogadro number (6.02.10²³)
n = m / MW
m = mass
MW = molecular weight
For density , can be formulated :
![\tt \rho=\dfrac{P\times MW}{R\times T}](https://tex.z-dn.net/?f=%5Ctt%20%5Crho%3D%5Cdfrac%7BP%5Ctimes%20MW%7D%7BR%5Ctimes%20T%7D)
P = 327 mmHg = 0,430263 atm
R = 0.082 L.atm / mol K
T = 48 ºC = 321.15 K
MW of H₂ = 2.015 g/mol
The density :
![\rho=\dfrac{0,430263\times 2.015 }{0.082\times 321.15}\\\\\rho=0.033~g/L](https://tex.z-dn.net/?f=%5Crho%3D%5Cdfrac%7B0%2C430263%5Ctimes%202.015%20%7D%7B0.082%5Ctimes%20321.15%7D%5C%5C%5C%5C%5Crho%3D0.033~g%2FL)
Question 9. The first one is the smallest. Anything with a negative exponent is going to be less than 1, the .00000241. The exponent tells you the number of zeroes to the right of the decimal point. Farther to right gets smaller and smaller.
Question 10. The last one is true. If the last digit is smaller than 5, drop the digit, and do not change. (If it is a 5 or larger, the digit before it would round up)