The first statement is true because s<span>peed, being a scalar quantity, is the rate at which an object covers distance. The average speed is the distance (a scalar quantity) per time ratio. Speed has nothing to do with direction. On the other hand, velocity is a vector quantity because direction is needed for this. </span>
Suppose the gas is ideal gas. According to the ideal gas equation of state, pV = nRT, the pressure is unchanged. So Vi/Ti = nR/p = Vn/Tn. (i stands for initial and n stands for new) So the new volume Vn = 3.67 L
Answer:
66.7 g
Explanation:
Number of atoms = 2×10²¹
Mass of 2×10²¹ atoms = 0.4 g
Mass of 0.5 moles of that element = ?
Solution:
1 mole contain 6.022×10²³ atoms
2×10²¹ atoms × 1 mol / 6.022×10²³ atoms
0.33×10⁻² mol
0.003 mol
0.003 mole have mass of 0.4 g
0.5 mol have mass 0.5/0.003×0.4 g = 66.7 g