Answer:
4.74 × 10³ mg
Explanation:
Given data
- Health risk limit for chloroform in groundwater: 60.0 g/L
- Volume of the sample of groundwater: 79.0 mL = 79.0 × 10⁻³ L
The maximum mass of chloroform that there could be in the sample of groundwater to meet the standards are:
79.0 × 10⁻³ L × 60.0 g/L = 4.74 g
1 gram is equal to 10³ milligrams. Then,
4.74 g × (10³ mg/1 g) = 4.74 × 10³ mg
The correct answer should be A.Ca and Br. A salt consists of a metal and a nonmetal, and a positive and negative charge. Ca (Calcium) is a metal and Br (Bromine) is a nonmetal, Ca is a +2 charge and Br is a -1 charge, so this is the only correct answer. Hope this helps :)
Answer:
b. The bromine (Br2) has reacted with the benzene, leaving fewer bromine molecules in solution.
Explanation:
Colour is caused by absorption of light of the frequency of “complementary colours”. Exactly which frequencies molecules absorb depends on the arrangement of electrons. Obviously, to break the Br-Br bond and the C=C bond in the reactants and replace them with two C-H bonds is a significant reordering of electrons and so the new molecule is no longer able to absorb the same frequencies as previously. Hence, a colour change, in this case from orange to colourless.
Newton's third law (for every action, there is an equal and opposite reaction) means that in every interaction (in this case, that of the objects in the image), there is a pair of forces acting on the two interacting objects. <span>When you sit on a chair, your body exerts a downward force on the chair and the chair exerts an upward force on your body. There are two forces resulting from this interaction - a force on the chair and a force on your body. This is embodied in the image by the two objects exerting force on each other (indicated by the arrows).</span><span>
Hope this helps.</span>
The correct option is 58 Fe 2+.
A neutral atom normally has the same number of proton, neutron and electrons, if the number of electrons differ from that of proton, that means that the elements has given some electrons away or it has gained some electrons from another element.
In the question given above, the atomic number of the element is 26 [because the proton number is 26], which means the element is iron. Iron has 24 electrons because it has given two away, so it will have +2. The iron has 32 neutrons instead of 26 so it is an isotope.