Ice, water and steam can exist simultaneously at:

Options

A. All temperatures
B. All pressures
C. All temperatures and pressure
D. Triple point

Explanation

To solve the question "Ice, water and steam can exist simultaneously at:", we can follow these steps:

### Step 1: Understand the States of Matter
Ice, water, and steam are the three states of water: solid, liquid, and gas, respectively. We need to find the condition under which all three can exist at the same time.

**Hint:** Recall the definitions of solid, liquid, and gas states of matter.

### Step 2: Introduce the Concept of the Phase Diagram
A phase diagram is a graphical representation that shows the state of a substance at various temperatures and pressures. It helps us understand the conditions under which different phases coexist.

**Hint:** Familiarize yourself with how a phase diagram is structured, especially for water.

### Step 3: Identify the Triple Point
In a phase diagram, the point where all three phases (solid, liquid, and gas) coexist is known as the "triple point." For water, this occurs at a specific temperature and pressure.

**Hint:** Look for the point on the phase diagram where the lines representing the different phases intersect.

### Step 4: Locate the Triple Point on the Phase Diagram
In the phase diagram of water, the triple point is located at approximately 0.01°C (273.16 K) and 0.00604 atm. At this point, ice, water, and steam can all exist together.

**Hint:** Remember that the triple point is a unique condition; it is not just any temperature and pressure.

### Step 5: Conclusion
Thus, the answer to the question is that ice, water, and steam can exist simultaneously at the "triple point."

**Final Answer:** D. Triple Point