Question

a. toxic
b. corrosive
c. flammable
d. biohazard

1. draw an nfpa diamond for a compound that poses a moderate health risk, is extremely flammable, is slightly reactive and is corrosive. (don’t forget to indicate the color needed!)
2. how many significant digits are there in the following numbers?

a. 0.00026 = 2
c. 1.26 x 10^6 =
b. 26,200 =
d. 1,265.0 = 5
e. 0.000600 = 3
g. 1.59 x 10^(-4) =
f. 4008 =
h. 4.950 x 10^2 =
i. 0.008 = 1
k. 4700 =

Explanation:

Step1: Recall significant - digit rules

Non - zero digits are always significant. Leading zeros (zeros before non - zero digits) are not significant. Trailing zeros in a number with a decimal point are significant. Trailing zeros in a whole number without a decimal point may or may not be significant (in scientific notation, the number of significant digits is clear from the coefficient).

Step2: Analyze 26,200

The non - zero digits 2, 6, and 2 are significant. The trailing zeros may or may not be significant depending on the precision. If no other information is given, we assume they are placeholders, so there are 3 significant digits.

Step3: Analyze 1.26×10⁶

The coefficient 1.26 has 3 non - zero digits, so there are 3 significant digits.

Step4: Analyze 4008

All non - zero digits and the zeros between non - zero digits are significant, so there are 4 significant digits.

Step5: Analyze 1.59×10⁻⁴

The coefficient 1.59 has 3 non - zero digits, so there are 3 significant digits.

Step6: Analyze 4.950×10²

The coefficient 4.950 has 4 digits, and the trailing zero is significant because of the decimal point, so there are 4 significant digits.

Step7: Analyze 4700

Without a decimal point, we assume the trailing zeros are placeholders, so there are 2 significant digits.

Answer:

a. 2
b. 3
c. 3
d. 5
e. 3
f. 4
g. 3
h. 4
i. 1
k. 2