Answer: The sun heats earth’s oceans causing convection currents to travel from the equator to the poles
Explanation: found it on a quizz thingy :D
Answer:- The average atomic mass or the atomic mass of the element is 69.7230 amu.
Solution:- The atomic mass or also known as average atomic mass of an element is calculated from it's isotopes by using the formula:
average atomic mass = mass of First isotope(abundance) + mass of second isotope(abundance)
From given data, the mass of first isotope is 68.9255 amu and mass of second isotope is 70.9247 amu. percent abundance for the first isotope is 60.11%. The sum of percent abundance of all the isotopes of an element is always 100. So, the percent abundance of second isotope = 100 - 60.11 = 39.89%
We convert the percent abundances to the decimals and then plug in the values in the formula to calculate the average atomic mass.
First isotope abundance = 0.6011
second isotope abundance = 0.3989
average atomic mass = 68.9255(0.6011) + 70.9247(0.3989)
average atomic mass = 41.4311 + 28.2919
average atomic mass = 69.7230 amu
So, the average atomic mass or the atomic mass of the element is 69.7230 amu.
Answer:
m = 1.3 Kg
Explanation:
according to Specific Heat Formula :
Q = mc∆T
when Q is the heat energy in Joules
m is the mass of water
C is the specific heat its unit J/kg∙K
∆T change in temperature (the final t - the initial t)
by substitution:
Q = 190000 g * 4.184 J/g∘C *78
Q = 62006880 J
when The combustion of 1.0 lb of oil provides 2.2×107J
So lb of oil when Q = 62006880 J = 2.8 Ib
and when 1lb=454g
So 2.8 Ib = 1271.2 g = 1.3 Kg
Answer:
0.109 g.
Explanation:
Equation of the reaction:
Na3PO4 + 3HCl --> 3NaCl + H3PO4
Number of moles of HCl = molar concentration × volume
= 0.1 × 0.04
= 0.004 mol.
By stoichiometry, 1 mole of Na3PO4 neutralises 3 moles of HCl. Therefore, number of moles of Na3PO4 = 0.004/3
= 0.0013 mol
Mass of Na3PO4 = molar mass × number of moles
= 0.0013 × 164
= 0.219 g
Since 50% of Na3PO4 was present in the sample. Let 100 g be the total mass of the substance
= 0.219 × 50 g/100 g
= 0.109 g.
