Copper is a good conductor of heat and electricity so it will not fry easily
948 or 9.48 x 10^2
There are two sets of rules for significant figures
• One set for addition and subtraction
• Another set for multiplication and division
You used the set for multiplication and division.
This problem involves addition and subtraction, and the rule is
The number of places after the decimal point in the answer must be <em>no greater than the number of decimal places in every term</em> in the sum.
Thus, we have
78.9
+890.43
-21.
= 948.33
The "21" term has the fewest digits after the decimal point (none), so the answer must have no digits after the decimal point.
To the correct answer is 948 = 9.48 x 10^2. It has three significant figures.
<span>the elements in groups1a, 2a, 3a have positive charges according to their group numbers</span>
Answer:
The correct answer is 5.0 L
Explanation:
STP are defined as T=273 K and P= 1 atm
By using the ideal gas equation, we can calculate the number of moles (n) of the gas at a volume V=2.5 L:
PV= nRT
⇒n= (PV)/(RT) =(1 atm x 2,5 L)/(0.082 L.atm/K.mol x 273 K)= 0.112 mol
For a sample of argon gas, with the same number of moles (0.112 mol) but twice the temperature (T = 273 K x 2= 546 K):
V= (nRT)/P = (0.112 mol x 0.082 L.atm/K.mol x 546 K)/1 atm = 5.0 L
That is consistent with the fact that when a gas is heated, it expanses. So, if the temperature increases twice, the volume also increases twice.
The answer is: " NaCl + H₂O " ; (or; write as: " H₂O + NaCl " ) .
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Specifically:
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HCl + NaOH —> NaCl + H₂O ; or; write as:
NaOH + HCl —> H₂O + NaCl .
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This type of "double-replacement" reaction is called "neutralization".
Since we are adding a strong acid to a strong base (reactants), we know that the product will be: 1) a salt ; and 2) water. Since we know one of the reactants will be "water" (H₂O) ; we can find the base (i.e. , the "remaining product") from selecting the "unused elements" to form the corresponding "salt".
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