Answer: 1,260
Explanation: There are about 180 days in a school year. 7 hour school days x 180 about 1,260
i hope this helps
Answer: D. Series circuits are simpler than parallel circuits.
Explanation:
In series circuit, all the components are connected in single path of current flow.
If one part of the circuit breaks, complete circuit would break and all the other parts also would not operate.
The voltage is not same everywhere. It is different across each component.
In series circuit, net resistance is more as resistance of all the components connected in series are added up.
So, the only advantage of a series circuit is that is simpler than the parallel circuits. Thus, the correct option is D.
Answer:
Mass of hydrogen gas evolved is 0.0749 grams.
Explanation:
Total pressure of the gases = p = 758 mmHg
Vapor pressure of water = 23.78 mmHg
Pressure of hydrogen gas ,P = p - 23.78 mmHg = 758 mmHg - 23.78 mmHg
P = 734.22 mmHg = 
Temperature of of hydrogen gas ,T= 25°C =298.15 K
Volume of hydrogen gas = V = 0.949 L
Moles of hydrogen gas =n
PV = nRT (Ideal gas equation )
n = 0.03745 mol
Moles of hydrogen gas = 0.03745 mol
Mass of 0.03745 moles of hydrogen gas = 0.03745 mol × 2 g/mol = 0.0749 g
Mass of hydrogen gas evolved is 0.0749 grams.
Answer:
32.1 × 10²³ formula units of CuCl₂
Explanation:
Given data:
Number of moles of CuCl₂ = 5.33 mol
Number of formula units of CuCl₂ = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
one mole of any substance contain 6.022 × 10²³ formula units thus,
5.33 moles of CuCl₂ = 5.33 ×6.022 × 10²³ formula units
32.1 × 10²³ formula units of CuCl₂
