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3 years ago

Express the sum of 9.78 g and 7.0 g using the correct number of significant digits.

Chemistry

2 answers:

Andrews [41]3 years ago

6 0

Answer is c because when we add the twi numbers we will get 16.78 and with significant
It will be 16.8

kvv77 [185]3 years ago

4 0

Answer:

The correct answer is 16.8 g (option C)

Explanation:

Step 1: Data given

9.78 grams + 7.0 grams

Rule significant numbers say:

⇒ Non-zero digits are always significant.

⇒ Any zeros between two significant digits are significant.

⇒ A final zero or trailing zeros in the decimal portion ONLY are significant.

For addition and subtraction, look at the places to the decimal point. Add or subtract in the normal way, then round the answer to the LEAST number of places to the decimal point of any number in the problem.

9.78 g+ 7.0 g = 16.78 grams

Significant numbers = 1 decimal

16.78 ⇒ 16.8

The correct answer is 16.8 g (option C)

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grin007 [14]

Answer:

21.28 grams solute can be added if the temperature is increased to 30.0°C.

Explanation:

Solubility of solute at 20°C = 32.2 g/100 grams of water

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Mass of solute in soluble in 56.0 grams of water at 30.0°C = 39.312 g

Mass of of solute added If the temperature of the saturated solution increased to 30.0°C:

39.312 g - 18.032 g = 21.28 g

21.28 grams solute can be added if the temperature is increased to 30.0°C.

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3 years ago

When a piece of metal is irradiated with UV radiation (λ = 162 nm), electrons are ejected with a kinetic energy of 3.54×10-19 J.

dsp73

We have that the work function of the metal

$\phi=1.227*10^{-18}J$

From the Question we are told that

UV radiation (λ = 162 nm)

Kinetic energy $K.E =3.54*10-19 J.$

Generally the equation for Kinetic energy is mathematically given as

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$\phi=1.227*10^{-18}J$

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ivolga24 [154]

Answer:

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