................... water
Answer:
Explanation:
An element whose atomic number is 68 (number Z), has 68 electrons and 68 protons. According to the periodic table it corresponds to the element Erbium (Er), whose mass number (A) is 167. The number of neutrons is 167-68 = 99.
A) The recursive formula for the number of seats in the n th row will be;
S1 = 9
S(n) = S (n-1) +2
b) Explicit formula; is that of an arithmetic progression; such that if a is the first term , and d is the common difference , then the n th term will be given by the formula: a + (n-1) d; where a is 9, and d is 2
Hence; for n th row = 9+ 2(n-1)
c) Number of seats in 12 th row using the formula in b.
n = 12 , a = 9, d = 2
therefore; 9 + 2(12-1)
= 9 + 2(11)
= 31 seats
Answer:
2.5 L.
Explanation:
- We can use the general law of ideal gas: <em>PV = nRT.</em>
where, P is the pressure of the gas in atm.
V is the volume of the gas in L.
n is the no. of moles of the gas in mol.
R is the general gas constant,
T is the temperature of the gas in K.
- If n and T are constant, and have two different values of V and P:
<em>P₁V₁ = P₂V₂
</em>
P₁ = 5.0 atm, V₁ = 3.5 L.
P₂ = 7.0 atm, V₂ = ??? L.
<em>∴ V₂ = P₁V₁/P₂ </em>= (5.0 atm)(3.5 L)/(7.0 atm) = <em>2.5 L.
</em>
Multiply moles by molar mass
9.83 g age