Answer:
1034 yrs
Explanation:
The equation to use in this question is:
t = -2.303/k log (A/A₀) where
A= present number of disintegrations
A₀ = intial number of disintegrations
k = decay constant
The decay constant we will obtain it from the given hal-life:
k: 0.693/t₁/₂, t₁/₂ = half-life ⇒
k: 0.693 / 5730 y = 1.209 x 10⁻⁴ /y⁻¹
t = - 2.303 / 1.209 x 10⁻⁴ /y⁻¹ x log (13.1/15.3) = 1034 yrs
Answer:
Shown below
Explanation:
a) for BrN3
80+3(14)=122amu
b) forC2H6
2(12) + 6(1) = 30amu
C) for NF2
14+2(19) = 52amu
D) Al2S3
2(27) + 3(32)= 150amu
E) for Fe(NO3)3
56 + 3 [14+3(16)] =242amu
F) Mg3N2
3(24) + 2(14)= 100amu
G) for (NH4)2CO3
2[14 +4(1)] +12 +3(16)=96amu
Answer:
1.75M
Explanation:
molarity = number of moles of solute/ number of L of solution =
=0.35 mol/0.2L = 1.75 mol/L = 1.75 M
Answer:
It is expressed as a multiple of one-twelfth the mass of the carbon-12 atom, 1.992646547 × 10−23 gram, which is assigned an atomic mass of 12 units. ... In this scale 1 atomic mass unit (amu) corresponds to 1.660539040 × 10−24 gram.
Answer:
11.7
Explanation:
The pH is the negative logarithm of the concentration of H+ ions. If the concentration is 2×10-¹² the the pH will be -log(2×10-¹²) which is 11.698 which can be round up to 11.7.
