Answer:
Reaction 1 is balanced but 2 is not balanced , the balance equation are :
1. 
2.
Explanation:
Balanced Equations : These are the equation which follows the law of conservation of mass .
The total number of atoms present in reactant is equal to total number of atoms present in product.
1. 
This is acid - base type reaction where
act as Acid
act as weak base
Reactant :
,
Number of atoms of :
C = 2 (
) + 1 (
)
= 2 + 1
= 3
H = 4(
) + 1 (
)
= 4 + 1
5
O = 2(
) + 3 (
)
= 5
Na = 1 (
)
= 1
Product :
,
, 
Number of atoms :
C = 1(
) + 2(
)
= 1 + 2
= 3
H = 2(
) + 3(
)
= 2 + 3
= 5
O = 1(
) + 2(
)
+2(
= 1 + 2 + 2
= 5
Na = 1(
= 1
Number of Na =1 , C = 3 , H= 5 and O =5 in both reactant and product , so it is a balanced reaction
2.
This is double displacement reaction .
Check the balancing in both reactant and products should be :
Na = 2
H = 2
Ca = 1
C = 2
O = 6
Cl = 2
I think the answer would be trenches but I’m sorry if I’m wrong
Answer:
See detailed answer with explanation below.
Explanation:
Valence electrons are electrons found on the outermost shell of an atom. They are the electrons in an atom that participate in chemical combination. Recall that the outermost shell of an atom is also referred to as its valence shell. Let us consider an example; if we look at the atom, sodium-11, its electronic configuration is 2,8,1. The last one electron is the valence electron of sodium which is found in its outermost or valence shell.
Positive ions are formed when electrons are lost from the valence shell of an atom. For instance, if the outermost electron in sodium is lost, we now form the sodium ion Na^+ which is a positive ion. Positive ions possess less number of electrons compared to their corresponding atoms.
Negative ions are formed when one or more electrons is added to the valence shell of an atom. A negative ion possesses more electrons than its corresponding atom. For example, chlorine(Cl) contains 17 electrons but the chloride ion (Cl^-) contains 18 electrons.
In molecular compounds, a bond is formed when two electrons are shared between the bonding atoms. Each bonding atom may contribute one of the shared electrons (ordinary covalent bond) or one of the bonding atoms may provide the both shared electrons (coordinate covalent bond). The shared pair may be located at an equidistant position to the nucleus of both atoms. Similarly, the electron may be drawn closer to the nucleus of one atom than the other (polar covalent bond) depending on the electro negativity of the two bonding atoms.
The electrons are shared in order to complete the octet of each atom by so doing, the both bonding atoms now obey the octet rule. For example, two chlorine atoms may come together to form a covalent bond in which each chlorine atom has an octet of electrons on its outermost shell.
Answer:
6.564×10¹⁶ fg.
Explanation:
The following data were obtained from the question:
Mass of beaker = 76.9 g
Mass of beaker + salt = 142.54 g
Mass of salt in fg =?
Next, we shall determine the mass of the salt in grams (g). This can be obtained as follow:
Mass of beaker = 76.9 g
Mass of beaker + salt = 142.54 g
Mass of salt =?
Mass of salt = (Mass of beaker + salt) – (Mass of beaker)
Mass of salt = 142.54 – 76.9
Mass of salt = 65.64 g
Finally, we shall convert 65.64 g to femtograms (fg) as illustrated below:
Recall:
1 g = 1×10¹⁵ fg
Therefore,
65.64 g = 65.64 g × 1×10¹⁵ fg / 1g
65.64 g = 6.564×10¹⁶ fg
Therefore, the mass of the salt is 6.564×10¹⁶ fg.
H3PO4 has molecular weight of approximately 98 grams per
mole. 4.50 M is equal to 4.50 mole per 1000 mL solution of H3PO4. 255 mL times
4.50 mol /1000 mL times 98 g/mol is equal to 112.455 grams. Note that I
automatically equate 1 Liter to 1000 mL since the given volume is in mL for
easier computation.