The only solution you'll need to have for this problem is a periodic table. The columns in the table are called groups, and they are number from the left to the right starting with 1. The rows in the table are called periods which are numbered from the top to bottom starting with 1.
6. Elements that belong to the same group portray similar chemical properties. Therefore, the element in period 4 which is also in group 2 is
<em>Calcium (Ca)</em>.
7. The elements that are striked through with the red slanting lines are the metalloids. All the elements to the left of the metalloids are metals. All the elements to the right are nonmetals. Bromine has a symbol of Br. Since At is a metalloid and located in the same group with Br, the
<em>answer is Astatine (At).</em>8. Tin has the chemical symbol of Sn. The nonmetal that is located in the same group is
<em>Carbon (C)</em>.
9. All the elements in period 6 would have similar properties. The answers could be:
<em>Phosphorus (P), Arsenic (As), Antimony (Sb) and Bismuth (Bi)</em>.
10. Period is row 1 and group 18 is the last column.
<em>The answer is Helium (He).</em>
Answer:
Mass= 2.77g
Explanation:
Applying
P=2.09atm, V= 1.13L, R= 0.082, T= 291K, Mm of N2= 28
PV=nRT
NB
Moles(n) = m/M
PV=m/M×RT
m= PVM/RT
Substitute and Simplify
m= (2.09×1.13×28)/(0.082×291)
m= 2.77g
0.53 x 200ml = 106 ml of the pH 9.0 buffer + 94 ml of the pH 10 buffer gives the desired solution
<span> </span>
Atomic mass Ni = 58.69 a.m.u
58.69 g ----------------- 6.02x10²³ atoms
?? g --------------------- 7.5x10¹⁵ atoms
58.69x (7.5x10¹⁵) / 6.02x10²³
=> 7.31x10⁻⁷ g
Answer:
protons
Explanation:
electron number changes when the atom reacts with another atom to gain a full octet
neutron number changes when it goes through radioactive decay
but proton number never changes