Answer:
the answer is b, 0.89
Explanation:
A cube has a height of 8 cm and a mass of 457 g. What is its density?
a. 233,984 g/cm
b. 0.89g/cm3
c. 1.12 g/cm3
Density = mass/volume
the volume of the cube is 8X8X8=512cm3
the mass is 457 gm
the density is 457/512 = 0.889 gm/cm3
the answer is b, 0.89
Answer:
5.6L
Explanation:
At STP, the pressure and temperature of an ideal gas is
P = 1 atm
T = 273.15k
Volume =?
Mass = 9.5g
From ideal gas equation,
PV = nRT
P = pressure
V = volume
n = number of moles
R = ideal gas constant =0.082J/mol.K
T = temperature of the ideal gas
Number of moles = mass / molar mass
Molar mass of F2 = 37.99g/mol
Number of moles = mass / molar mass
Number of moles = 9.5 / 37.99
Number of moles = 0.25moles
PV = nRT
V = nRT/ P
V = (0.25 × 0.082 × 273.15) / 1
V = 5.599L = 5.6L
The volume of the gas is 5.6L
Answer:
Explanation:
Accoding to the First Law of Thermodynamics, the heat released by the water melts a portion of ice. That is to say:
The amount of ice that is melt is:
The mass for of aluminum that is produced by the decomposition of 5.0 Kg Al2O3 is 2647 g or 2.647 Kg
calculation
Write the equation for decomposition of Al2O3
Al2O3 = 2Al + 3 O2
find the moles of Al2O3 = mass/molar mass
convert 5 Kg to g = 5 x1000 = 5000 grams
molar mass of Al2O3 = 27 x2 + 16 x3 = 102 g/mol
moles =5000 g/ 102 g/mol = 49.0196 moles
by use of mole ratio between Al2O3 to Al which is 1:2 the moles of Al = 49.0196 x2 =98.0392 moles
mass of Al = moles x molar mass
= 98.0392 moles x 27g/mol = 2647 grams or 2647/1000 = 2.647 Kg
Answer:
greenhouse effect is the same as global warming
Explanation:
they both mean warming of the earths surface
